Configuring Port Channels
Configuring Port Channels
This chapter describes how to configure port channels.
• Finding Feature Information, page 1
• Feature History for Configuring Port Channels, page 1
• Licensing Requirements for Port Channels, page 2
• Prerequisites for Port Channeling, page 3
• Guidelines and Limitations for Port Channels, page 3
• Default Settings, page 4
• Information About Port Channels, page 5
• Configuring Port Channels, page 19
• Configuring Random Load Balance , page 43
• Verifying Port-Channel Configurations, page 45
• Monitoring the Port-Channel Interface Configuration, page 46
• Configuration Examples for Port Channels, page 47
• Related Documents, page 47
Finding Feature Information
Your software release might not support all the features documented in this module. For the latest caveats
and feature information, see the Bug Search Tool at https://tools.cisco.com/bugsearch/ and the release notes
for your software release. To find information about the features documented in this module, and to see a list
of the releases in which each feature is supported, see the “New and Changed Information” chapter or the
Feature History table in this chapter.
Feature History for Configuring Port Channels
This table includes only the updates for those releases that have resulted in additions or changes to the feature.
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Configuring Port Channels
Licensing Requirements for Port Channels
Feature Name
Release
Feature Information
Port Channels Hash
Distribution
8.(0)1
Added support for port channels hash
distribution on M3 modules.
GPRS Tunneling Protocol
7.3(0)DX(1)
(GTP) Load Balance Support
on M3-Series Modules
Improved port-channel and ECMP load
balancing for GTP traffic with M3 modules.
Random Load Balance (Port 7.3(0)D1(1)
Channel)
Added support for Random Load Balancing
on port channels. Added the random keyword
to port-channel load-balance command to
improve load balancing across port channels.
DisplayPpolicy Errors on
Interfaces and VLANs
6.2(2)
Added the show interface status error policy
command.
Prevent Traffic-Drop During 6.2(2)
Bi-Directional Flow on F2 or
F2e Modules
Added the asymmetric keyword to
port-channel load-balance command to
improve load balancing across port channels.
Result Bundle Hash Load
Balancing
6.1(3)
Support for the RBH modulo mode to
improve load balancing across port channels.
Minimum Links for FEX
Fabric Port Channel
6.1(3)
This feature was introduced.
Port Channels Hash
Distribution
6.1(1)
Support for port channel hash distribution
fixed and adaptive mode.
Load-Balancing Supports F2 6.0(1)
Modules
Added support for F2 modules on
load-balancing across port channels.
Port Channels
5.2(1)
Support increased to 528 port channels.
Minimum Links and
Maxbundle for LACP
5.1(1)
This feature was introduced.
Port Channels
4.2(1)
Support increased to 256 port channels.
Port Channels
4.0(1)
This feature was introduced.
Licensing Requirements for Port Channels
vPC requires no license. Any feature not included in a license package is bundled with the Cisco NX-OS
system images and is provided at no extra charge to you. For a complete explanation of the Cisco NX-OS
licensing scheme, see the Cisco NX-OS Licensing Guide.
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Configuring Port Channels
Prerequisites for Port Channeling
IP tunnels require an Enterprise Services license. For a complete explanation of the Cisco NX-OS licensing
scheme and how to obtain and apply licenses, see the Cisco NX-OS Licensing Guide.
All other interfaces do not require a license.
Prerequisites for Port Channeling
Port channeling has the following prerequisites:
• You must be logged onto the device.
• If necessary, install the Advanced Services license and enter the desired VDC.
• All ports in the channel group must be in the same VDC.
• All ports for a single port channel must be either Layer 2 or Layer 3 ports.
• All ports for a single port channel must meet the compatibility requirements. See the “Compatibility
Requirements” section for more information about the compatibility requirements.
• You must configure load balancing from the default VDC.
Guidelines and Limitations for Port Channels
Port channeling has the following configuration guidelines and limitations:
• The LACP port-channel minimum links and maxbundle feature is not supported for host interface port
channels.
• You must enable LACP before you can use that feature.
• You can configure multiple port channels on a device.
• Do not put shared and dedicated ports into the same port channel. (See “Configuring Basic Interface
Parameters,” for information about shared and dedicated ports.)
• For Layer 2 port channels, ports with different STP port path costs can form a port channel if they are
compatibly configured with each other. See the “Compatibility Requirements” section for more information
about the compatibility requirements.
• In STP, the port-channel cost is based on the aggregated bandwidth of the port members.
• After you configure a port channel, the configuration that you apply to the port-channel interface affects
the port-channel member ports. The configuration that you apply to the member ports affects only the
member port where you apply the configuration.
• LACP does not support half-duplex mode. Half-duplex ports in LACP port channels are put in the
suspended state.
• You must remove the port-security information from a port before you can add that port to a port channel.
Similarly, you cannot apply the port-security configuration to a port that is a member of a channel group.
• Do not configure ports that belong to a port-channel group as private VLAN ports. While a port is part
of the private VLAN configuration, the port-channel configuration becomes inactive.
• Channel member ports cannot be a source or destination SPAN port.
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Default Settings
• You cannot configure the ports from an F1- and an M1-series module in the same port channel because
the ports will fail to meet the compatibility requirements.
• You cannot configure the ports from an M1- and M2-series module in the same port channel.
• You cannot configure the ports from an F2e- and an F3-series module in the same port channel because
the ports will fail to meet the compatibility requirements.
• From Cisco NX-OS Release 5.1, you can bundle up to 16 active links into a port channel on the F1-series
module.
• F1-series modules do not support load balancing of non-IP traffic based on a MAC address. If ports on
an F1-series module are used in a port channel and non-IP traffic is sent over the port channel, Layer 2
traffic might get out of order.
• Only F series and the XL type of M-series modules support the RBH modulo mode.
• Random load balance on port channel is supported only on F3-series modules. Ensure both sides of the
port channel are F3 modules only.
Default Settings
Table 1: Default Port-Channel Parameters
Parameter
Default
Port channel
Admin up
Load-balancing method for Layer 3 interfaces
Source and destination IP address
Load-balancing method for Layer 2 interfaces
Source and destination MAC address
Load balancing per module
Disabled
RBH modulo mode
Disabled
LACP
Disabled
Channel mode
on
LACP system priority
32768
LACP port priority
32768
Minimum links for LACP
1
Maxbundle
16
Minimum links for FEX fabric port channel
1
Random load balancing (port channels)
Disabled
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Configuring Port Channels
Information About Port Channels
Information About Port Channels
A port channel is an aggregation of multiple physical interfaces that creates a logical interface. You can bundle
up to 8 individual active links into a port channel to provide increased bandwidth and redundancy. If a member
port within a port channel fails, the traffic previously carried over the failed link switches to the remaining
member ports within the port channel. Port channeling also load balances traffic on the M series module and
across these physical interfaces. The port channel stays operational as long as at least one physical interface
within the port channel is operational.
Note
From Cisco NX-OS Release 5.1, you can bundle up to 16 active links into a port channel on the F-series
module.
You cannot configure a shared interface to be part of a port channel. See the Cisco NX-OS FCoE Configuration
Guide for Cisco Nexus 7000 and Cisco MDS 9000Cisco NX-OS FCoE Configuration Guide for Cisco Nexus
7000 and Cisco MDS 9000 for more information about shared interfaces.
You can bundle up to 8 ports into a static port channel without using any aggregation protocol. On the M-series
module, you can bundle up to 8 active and 8 standby on the M-series module and up to 16 ports on the F
Series module.
However, you can enable the LACP to use port channels more flexibly. Configuring port channels with LACP
and static port channels require a slightly different procedure.
Note
This device does not support Port Aggregation Protocol (PAgP) for port channels.
Each port can be in only one port channel. All the ports in a port channel must be compatible; they must use
the same speed and duplex mode (see the “Compatibility Requirements” section). When you run static port
channels with no aggregation protocol, the physical links are all in the on channel mode; you cannot change
this mode without enabling LACP (see the “Port-Channel Modes” section).
You can create port channels directly by creating the port-channel interface, or you can create a channel group
that acts to aggregate individual ports into a bundle. When you associate an interface with a channel group,
the software creates a matching port channel automatically if the port channel does not already exist. In this
instance, the port channel assumes the Layer 2 or Layer 3 configuration of the first interface. You can also
create the port channel first. In this instance, the Cisco NX-OS software creates an empty channel group with
the same channel number as the port channel and takes the default Layer 2 or Layer 3 configuration, as well
as the compatibility configuration (see the “Compatibility Requirements” section). See “Configuring Layer 3
Interfaces,” for more information about creating and deleting port-channel subinterfaces.
Note
The port channel is operationally up when at least one of the member ports is up and that port’s status is
channeling. The port channel is operationally down when all member ports are operationally down.
You can create a Layer 2 port channel by bundling compatible Layer 2 interfaces, or you can create Layer 3
port channels by bundling compatible Layer 3 interfaces. After you create a Layer 3 port channel, you can
add an IP address to the port-channel interface and create subinterfaces on the Layer 3 port channel. You
cannot combine Layer 2 and Layer 3 interfaces in the same port channel.
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Configuring Port Channels
Information About Port Channels
From Cisco NX-OS Release 4.2, you can apply port security to port channels. See the Cisco Nexus 7000
Series NX-OS Security Configuration GuideCisco Nexus 7000 Series NX-OS Security Configuration Guide
for information about port security. All ports in the port channel must be in the same virtual device context
(VDC); you cannot configure port channels across VDCs.
You can also change the port channel from Layer 3 to Layer 2. See “Configuring Layer 2 Interfaces,” for
information about creating Layer 2 interfaces.
Any configuration changes that you apply to the port channel are applied to each member interface of that
port channel. For example, if you configure Spanning Tree Protocol (STP) parameters on the port channel,
the Cisco NX-OS software applies those parameters to each interface in the port channel.
Note
After a Layer 2 port becomes part of a port channel, all switchport configurations must be done on the
port channel; you can no longer apply switchport configurations to individual port-channel members. You
cannot apply Layer 3 configurations to an individual port-channel member either; you must apply the
configuration to the entire port channel.
You can create subinterfaces on a Layer 3 port channel, even though a subinterface is part of the logical
port-channel interface. See the “Subinterfaces” section for more information about port-channel subinterfaces.
You can use static port channels, with no associated aggregation protocol, for a simplified configuration. For
more flexibility, you can use the Link Aggregation Control Protocol (LACP), which is defined in IEEE
802.3ad. When you use LACP, the link passes protocol packets. You cannot configure LACP on shared
interfaces.
See the “LACP” section for information about LACP.
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Configuring Port Channels
Port-Channel Interfaces
Port-Channel Interfaces
The figure below shows port-channel interfaces.
Figure 1: Port-Channel Interfaces
You can classify port-channel interfaces as Layer 2 or Layer 3 interfaces. In addition, you can configure Layer
2 port channels in either access or trunk mode. Layer 3 port-channel interfaces have routed ports as channel
members and might have subinterfaces.
From Cisco NX-OS Release 4.2(1), you can configure a Layer 3 port channel with a static MAC address. If
you do not configure this value, the Layer 3 port channel uses the router MAC of the first channel member
to come up. See the Cisco Nexus 7000 Series NX-OS Layer 2 Switching Configuration GuideCisco Nexus
7000 Series NX-OS Layer 2 Switching Configuration Guide for information about configuring static MAC
addresses on Layer 3 port channels.
See “Configuring Layer 2 Interfaces,” for information about configuring Layer 2 ports in access or trunk mode
and “Configuring Layer 3 Interfaces,” for information about configuring Layer 3 interfaces and subinterfaces
.
Basic Settings
You can configure the following basic settings for a port-channel interface:
• Bandwidth—Use this setting for informational purposes only; this setting is to be used by higher-level
protocols.
• Delay—Use this setting for informational purposes only; this setting is to be used by higher-level
protocols.
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Compatibility Requirements
• Interface Description—Use this setting to provide a unique name for each interface so that you can
quickly identify the interface when you are looking at a listing of multiple interfaces.
• Duplex—By default, each interface autonegotiates its duplex mode with the other interface, but you can
change these settings. If you change the settings, be sure to use the same duplex mode setting on both
interfaces, or use autonegotiation for at least one of the interfaces.
• Flow control—Use this setting to allow flow control to work between two ports. You must set the
corresponding receive and send flow control parameters for both ports as enabled or desired.
• IP addresses—Both IPv4 and IPv6
• Maximum Transmission Unit (MTU)—Use this setting to specify the maximum frame size that an
Ethernet port can process.
• Shutdown—Use this setting to bring down or up an interface.
• Speed—By default, each interface autonegotiates its speed mode with the other interface, but you can
change these settings. If you change the settings, be sure to use the same speed mode setting on both
interfaces, or use autonegotiation for at least one of the interfaces.
Compatibility Requirements
When you add an interface to a channel group, the software checks certain interface attributes to ensure that
the interface is compatible with the channel group. For example, you cannot add a Layer 3 interface to a Layer
2 channel group. The Cisco NX-OS software also checks a number of operational attributes for an interface
before allowing that interface to participate in the port-channel aggregation.
The compatibility check includes the following operational attributes:
• (Link) speed capability
• Access VLAN
• Allowed VLAN list
• Check rate mode
• Duplex capability
• Duplex configuration
• Flow-control capability
• Flow-control configuration
• Layer 3 ports—(Cannot have subinterfaces)
• MTU size
• Media type, either copper or fiber
• Module Type
• Network layer
• Port mode
• SPAN—(Cannot be a SPAN source or a destination port)
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Configuring Port Channels
Compatibility Requirements
• Speed configuration
• Storm control
• Tagged or untagged
• Trunk native VLAN
Use the show port-channel compatibility-parameters command to see the full list of compatibility checks
that the Cisco NX-OS uses.
You can only add interfaces configured with the channel mode set to on to static port channels, and you can
only add interfaces configured with the channel mode as active or passive to port channels that are running
LACP. You can configure these attributes on an individual member port. If you configure a member port with
an incompatible attribute, the software suspends that port in the port channel.
Alternatively, you can force ports with incompatible parameters to join the port channel if the following
parameters are the same:
• (Link) Speed capability
• Speed configuration
• Duplex capability
• Duplex configuration
• Flow-control capability
• Flow-control configuration
When the interface joins a port channel, some of its individual parameters are removed and replaced with the
values on the port channel as follows:
• Bandwidth
• Delay
• Extended Authentication Protocol over UDP
• VRF
• IP address (v4 and v6)
• MAC address
• Spanning Tree Protocol
• NAC
• Service policy
• Access control lists (ACLs)
Many interface parameters remain unaffected when the interface joins or leaves a port channel as follows:
• Beacon
• Description
• CDP
• LACP port priority
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Configuring Port Channels
Load Balancing Using Port Channels
• Debounce
• UDLD
• MDIX
• Rate mode
• Shutdown
• SNMP trap
If you configure subinterfaces for the port-channel interface and remove a member port from the port channel,
the configuration of the port-channel subinterface does not propagate to the member ports.
Note
When you delete the port channel, the software sets all member interfaces as if they were removed from
the port channel.
See the “LACP Marker Responders” section for information about port-channel modes.
Load Balancing Using Port Channels
The Cisco NX-OS software load balances traffic across all operational interfaces in a port channel by hashing
the addresses in the frame to a numerical value that selects one of the links in the channel. Port channels
provide load balancing by default. Port-channel load balancing uses MAC addresses, IP addresses, or Layer
4 port numbers to select the link. Port-channel load balancing uses either source or destination addresses or
ports, or both source and destination addresses or ports.
You can configure the load-balancing mode to apply to all port channels that are configured on the entire
device or on specified modules. The per-module configuration takes precedence over the load-balancing
configuration for the entire device. You can configure one load-balancing mode for the entire device, a different
mode for specified modules, and another mode for the other specified modules. You cannot configure the
load-balancing method per port channel.
You can configure the type of load-balancing algorithm used. You can choose the load-balancing algorithm
that determines which member port to select for egress traffic by looking at the fields in the frame.
Note
The default load-balancing mode for Layer 3 interfaces is the source and destination IP address, and the
default load-balancing mode for non-IP traffic is the source and destination MAC address. Use the
port-channel load-balance command to set the load-balancing method among the interfaces in the
channel-group bundle. The default method for Layer 2 packets is src-dst-mac. The default method for
Layer 3 packets is src-dst-ip. For additional information about this command, see the Cisco Nexus 7000
Series NX-OS Interfaces Command Reference.
F1-series modules do not support load balancing of non-IP traffic based on a MAC address. If ports on
an F1-series module are used in a port channel and non-IP traffic is sent over the port channel, Layer 2
traffic might get out of order. From Cisco NX-OS Release 6.0(1), load balancing supports F2 modules.
You can configure the device to use one of the following methods to load balance across the port channel:
• Destination MAC address
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Configuring Port Channels
Symmetric Hashing
• Source MAC address
• Source and destination MAC address
• Destination IP address
• Source IP address
• Source and destination IP address
• Source TCP/UDP port number
• Destination TCP/UDP port number
• Source and destination TCP/UDP port number
Non-IP and Layer 3 port channels both follow the configured load-balancing method, using the source,
destination, or source and destination parameters. For example, when you configure load balancing to use the
source IP address, all non-IP traffic uses the source MAC address to load balance the traffic while the Layer
3 traffic load balances the traffic using the source IP address. Similarly, when you configure the destination
MAC address as the load-balancing method, all Layer 3 traffic uses the destination IP address while the non-IP
traffic load balances using the destination MAC address.
Note
You cannot configure load balancing using port channels per virtual device context (VDC). You must be
in the default VDC to configure this feature; if you attempt to configure this feature from another VDC,
the system displays an error.
You can configure load balancing either by the entire system or by specific modules, regardless of the VDC.
The port-channel load balancing is a global setting across all VDCs.
If the ingress traffic is Multiprotocol Label Switching (MPLS) traffic, the software looks under the labels for
the IP address on the packet.
Multicast traffic inherits the same port-channel load balancing configuration as unicast traffic. This is applicable
for both system-wide and module-specific load balancing configurations.
Note
Devices that run Cisco IOS can optimize the behavior of the member ports of ASICs if a failure of a single
member occurred if you enter the port-channel hash-distribution command. The Cisco Nexus 7000
Series device performs this optimization by default and does not require or support this command. Cisco
NX-OS does support the customization of the load-balancing criteria on port channels through the
port-channel load-balance command either for the entire device or on a per-module basis. See the Cisco
Nexus 7000 Series NX-OS Interfaces Command Reference for information about this command.
Cisco NX-OS Release 6.1(3) supports a new Result Bundle Hash (RBH) mode to improve load balancing on
port-channel members on Cisco Nexus 7000 M Series I/O XL modules and on F Series modules. With the
new RBH modulo mode, the RBH result is based on the actual count of port-channel members.
Symmetric Hashing
To effectively monitor traffic on a port channel, it is essential that each interface connected to a port channel
receives both forward and reverse traffic flows. Normally, there is no guarantee that the forward and reverse
traffic flows will use the same physical interface. However, when you enable symmetric hashing on the port
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Configuring Port Channels
Random Load Balancing (Port Channel)
channel, bidirectional traffic is forced to use the same physical interface and each physical interface in the
port channel is effectively mapped to a set of flows.
When symmetric hashing is enabled, the parameters used for hashing, such as the source and destination IP
address, are normalized before they are entered into the hashing algorithm. This process ensures that when
the parameters are reversed (the source on the forward traffic becomes the destination on the reverse traffic),
the hash output is the same. Therefore, the same interface is chosen.
Only the following load-balancing algorithms support symmetric hashing:
• src ip
• dst ip rotate
• dst ip
• src ip rotate
• src-dst ip
• src ip-l4port
• dst ip-l4port rotate
• dst ip-l4port
• src ip-l4port rotate
• src-dst ip-l4port-vlan
• dst ip-vlan
• src ip-vlan rotate
• src-dst ip-vlan
• src l4port
• dst l4port rotate
• dst l4port
• src l4port rotate
• src-dst l4port
• src mac
• dst mac rotate
• dst mac
• src mac rotate
• src-dst mac
Random Load Balancing (Port Channel)
Random load balancing on port channels is a software solution that enables better port-link bandwidth utilization
for GPRS Tunneling Protocol (GTP) over IP-UDP packets. The existing M1, M2, F1, F2 and F2e line card
hardware does not have the capability to perform random load balancing and hence, this software solution
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Configuring Port Channels
LACP
helps in load balancing and optimizing the port channels bandwidth. Random load balancing is supported
only on F3 series line cards. Random load balancing is applicable on all types of traffic and is effective on
egress ports of Layer 3 traffic. The Cisco NX-OS software does random load balancing of all traffic across
all interfaces in a port channel by using polynomial scheme.
LACP
LACP allows you to configure up to 16 interfaces into a port channel. A maximum of 8 interfaces can be
active, and a maximum of 8 interfaces can be placed in a standby state on the M-series modules.
From Cisco NX-OS Release 5.1, you can bundle up to 16 active links into a port channel on the F-Series
module.
Note
You must enable LACP before you can use LACP. By default, LACP is disabled.
See the “Enabling LACP” section for information about enabling LACP.
From Cisco NX-OS Release 4.2, the system automatically takes a checkpoint before disabling the feature,
and you can roll back to this checkpoint. See the Cisco Nexus 7000 Series NX-OS System Management
Configuration GuideCisco Nexus 7000 Series NX-OS System Management Configuration Guide for information
about rollbacks and checkpoints.
The figure below shows how individual links can be combined into LACP port channels and channel groups
as well as function as individual links.
Figure 2: Individual Links Combined into a Port Channel
With LACP, you can bundle up to 16 interfaces in a channel group. If the channel group has more than 8
interfaces, the remaining interfaces are in hot standby for the port channel associated with this channel group
on the M-series modules.
From Cisco NX-OS Release 5.1, you can bundle up to 16 active links into a port channel on the F-series
module.
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Configuring Port Channels
LACP
Note
When you delete the port channel, the software automatically deletes the associated channel group. All
member interfaces revert to their original configuration.
You cannot disable LACP while any LACP configurations are present.
Port-Channel Modes
Individual interfaces in port channels are configured with channel modes. When you run static port channels
with no aggregation protocol, the channel mode is always set to on.
After you enable LACP globally on the device, you enable LACP for each channel by setting the channel
mode for each interface to active or passive. You can configure either channel mode for individual links in
the LACP channel group when you are adding the links to the channel group.
Note
You must enable LACP globally before you can configure an interface in either the active or passive
channel mode.
Table 2: Port-Channel Modes
Channel Mode
Description
passive
LACP mode that places a port into a passive negotiating state in which the
port responds to LACP packets that it receives but does not initiate LACP
negotiation.
active
LACP mode that places a port into an active negotiating state in which the
port initiates negotiations with other ports by sending LACP packets.
on
All static port channels (that are not running LACP) remain in this mode.
If you attempt to change the channel mode to active or passive before
enabling LACP, the device displays an error message.
You enable LACP on each channel by configuring the interface in that
channel for the channel mode as either active or passive. When an LACP
attempts to negotiate with an interface in the on state, it does not receive
any LACP packets and becomes an individual link with that interface; it
does not join the LACP channel group.
The default port-channel mode is on.
Both the passive and active modes allow LACP to negotiate between ports to determine if they can form a
port channel based on criteria such as the port speed and the trunking state. The passive mode is useful when
you do not know whether the remote system, or partner, supports LACP.
Ports can form an LACP port channel when they are in different LACP modes if the modes are compatible
as seen in these examples:
• A port in active mode can form a port channel successfully with another port that is in active mode.
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LACP
• A port in active mode can form a port channel with another port in passive mode.
• A port in passive mode cannot form a port channel with another port that is also in passive mode, because
neither port will initiate negotiation.
• A port in on mode is not running LACP and cannot form a port channel with another port that is in active
or passive mode.
LACP ID Parameters
LACP System Priority
Each system that runs LACP has an LACP system priority value. You can accept the default value of 32768
for this parameter, or you can configure a value between 1 and 65535. LACP uses the system priority with
the MAC address to form the system ID and also uses the system priority during negotiation with other devices.
A higher system priority value means a lower priority.
The system ID is different for each VDC.
Note
The LACP system ID is the combination of the LACP system priority value and the MAC address.
LACP Port Priority
Each port that is configured to use LACP has an LACP port priority. You can accept the default value of
32768 for the LACP port priority, or you can configure a value between 1 and 65535. LACP uses the port
priority with the port number to form the port identifier.
LACP uses the port priority to decide which ports should be put in standby mode when there is a limitation
that prevents all compatible ports from aggregating and which ports should be put into active mode. A higher
port priority value means a lower priority for LACP. You can configure the port priority so that specified
ports have a lower priority for LACP and are most likely to be chosen as active links, rather than hot-standby
links.
LACP Administrative Key
LACP automatically configures an administrative key value equal to the channel-group number on each port
configured to use LACP. The administrative key defines the ability of a port to aggregate with other ports. A
port’s ability to aggregate with other ports is determined by these factors:
• Port physical characteristics, such as the data rate and the duplex capability
• Configuration restrictions that you establish
LACP Marker Responders
You can dynamically redistribute the data traffic by using port channels. This redistribution might result from
a removed or added link or a change in the load-balancing scheme. Traffic redistribution that occurs in the
middle of a traffic flow can cause misordered frames.
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LACP
LACP uses the Marker Protocol to ensure that frames are not duplicated or reordered due to this redistribution.
The Marker Protocol detects when all the frames of a given traffic flow are successfully received at the remote
end. LACP sends Marker PDUs on each of the port-channel links. The remote system responds to the Marker
PDU once it receives all the frames received on this link prior to the Marker PDU. The remote system then
sends a Marker Responder. Once the Marker Responders are received by the local system on all member links
of the port channel, the local system can redistribute the frames in the traffic flow with no chance of misordering.
The software supports only Marker Responders.
Differences Between LACP-Enabled Port Channels and Static Port Channels
The table below summarizes the major differences between port channels with LACP enabled and static port
channels.
Table 3: Differences Between LACP-Enabled Port Channels and Static Port Channels
Configuration
Port Channels with LACP Enabled Static Port Channels
Protocol applied
Enable globally
Not applicable
Channel mode of links
Can be either:
Can only be On
• Active
• Passive
Maximum number of links in
channel
16
8
LACP Compatibility Enhancements
Several new commands have been added in Release 4.2(3) to address interoperability issues and to assist with
faster LACP protocol convergence.
When a Cisco Nexus 7000 Series device is connected to a non-Nexus peer, its graceful failover defaults may
delay the time taken for a disabled port to be brought down or cause traffic from the peer to be lost. To address
these conditions, the lacp graceful-convergence command was added.
By default, LACP sets a port to the suspended state if it does not receive an LACP PDU from the peer. In
some cases, although this feature helps in preventing loops created due to misconfigurations, it can cause
servers to fail to boot up because they require LACP to logically bring up the port. You can put a port into an
individual state by using the lacp suspend-individual command.
LACP Port-Channel Minimum Links and MaxBundle
A port channel aggregates similar ports to provide increased bandwidth in a single manageable interface.
With the Cisco NX-OS Release 5.1, the introduction of the minimum links and maxbundle feature further
refines LACP port-channel operation and provides increased bandwidth in one manageable interface.
The LACP port-channel minimum links feature does the following:
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Configuring Port Channels
Minimum Number of Links on the FEX Fabric Port Channel
• Configures the minimum number of ports that must be linked up and bundled in the LACP port channel.
• Prevents the low-bandwidth LACP port channel from becoming active.
• Causes the LACP port channel to become inactive if there are few active members ports to supply the
required minimum bandwidth.
The LACP MaxBundle defines the maximum number of bundled ports allowed in a LACP port channel.
The LACP MaxBundle feature does the following:
• Defines an upper limit on the number of bundled ports in an LACP port channel.
• Allows hot-standby ports with fewer bundled ports. (For example, in an LACP port channel with five
ports, you can designate two of those ports as hot-standby ports.)
Note
The minimum links and maxbundle feature works only with LACP port channels. However, the device
allows you to configure this feature in non-LACP port channels, but the feature is not operational.
LACP Offload to Fabric Extenders
To reduce the load on the control plane of the Cisco Nexus 7000 Series device, Cisco NX-OS provides the
ability to offload link-level protocol processing to the Fabric Extender CPU. This feature is supported by
LACP by default as soon as there is at least one LACP port channel configured on a Fabric Extender.
LACP Fast Timers
You can change the LACP timer rate to modify the duration of the LACP timeout. Use the lacp rate command
to set the rate at which LACP control packets are sent to an LACP-supported interface. You can change the
timeout rate from the default rate (30 seconds) to the fast rate (1 second). This command is supported only
on LACP-enabled interfaces. To configure the LACP fast time rate, see the “Configuring the LACP Fast Timer
Rate” section.
ISSU and stateful switchover cannot be guaranteed with LACP fast timers.
Minimum Number of Links on the FEX Fabric Port Channel
In a network configuration of dual-homed hosts (active/standby), you can configure the Cisco Nexus 2000
Series Fabric Extender (FEX) to support a minimum number of links for fabric port channels.
When the number of fabric port-channel links falls below the specified threshold, the host-facing FEX interfaces
are brought down, which allows for a NIC switchover on the connection between the host and the FEX. The
automatic recovery of the FEX interfaces to the standby FEX is triggered when the number of fabric
port-channel links reaches the specified threshold.
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Configuring Port Channels
Virtualization Support
Virtualization Support
You must configure the member ports and other port-channel related configuration from the virtual device
context (VDC) that contains the port channel and member ports. You can use the numbers from 1 to 4096 in
each VDC to number the port channels and you can reuse these port-channel numbers in different VDCs. For
example, you can configure port channel 100 in VDC1 and also configure a different port channel 100 in
VDC2.
However, the LACP system ID is different for each VDC. For more information about LACP, see the “LACP”
section.
Note
See the Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration GuideCisco Nexus 7000
Series NX-OS Virtual Device Context Configuration Guidefor complete information about VDCs and
assigning resources.
All ports in one port channel must be in the same VDC. When you are using LACP, all possible 8 active ports
and all possible 8 standby ports must be in the same VDC. The port channels can originate in one VDC (with
all ports in that channel in the same VDC) and partner with a port channel in another VDC (again, all ports
in that channel must be in that VDC).
Note
The port-channeling load-balancing mode works either for a single module or across the entire device.
You must configure load balancing using port channels in the default VDC. You cannot configure load
balancing using port channels within specified VDCs. See the “Load Balancing Using Port Channels”
section for more information about load balancing.
High Availability
Port channels provide high availability by load balancing traffic across multiple ports. If a physical port fails,
the port channel is still operational if there is an active member in the port channel. You can bundle ports
from different modules and create a port channel that remains operational even if a module fails because the
settings are common across the module.
Port channels support stateful and stateless restarts. A stateful restart occurs on a supervisor switchover. After
the switchover, the Cisco NX-OS software applies the runtime configuration after the switchover.
The port channel goes down if the operational ports fall below the configured minimum links number.
Note
See the Cisco Nexus 7000 Series NX-OS High Availability and Redundancy Guide for complete information
about high-availability features.
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Configuring Port Channels
Configuring Port Channels
Configuring Port Channels
Creating a Port Channel
You can create a port channel before you create a channel group. The software automatically creates the
associated channel group.
Before You Begin
• Enable LACP if you want LACP-based port channels.
• Before you configure this feature for the entire system, ensure that you are in the correct VDC. To change
the VDC, use the switchto vdc command.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
port-channel channel-number
Specifies the port-channel interface to configure, and enters
the interface configuration mode. The range is from 1 to
4096. The Cisco NX-OS software automatically creates the
channel group if it does not already exist.
Step 3
switch(config-if)# show
port-channel summary
Displays information about the port channel.
Step 4
switch(config-if)# show interface (Optional)
Displays the interfaces and VLANs that produce an error
status error policy [detail]
during policy programming to ensure that policies are
consistent with hardware policies.
Use the detail command to display the details of the
interfaces that produce an error.
Step 5
switch(config-if)# no shutdown
(Optional)
Clears the errors on the interfaces and VLANs where policies
correspond with hardware policies. This command allows
policy programming to continue and the port to come up. If
policies do not correspond, the errors are placed in an
error-disabled policy state.
Step 6
switch(config-if)# copy
running-config startup-config
(Optional)
Copies the running configuration to the startup configuration.
Use the no interface port-channel command to remove the port channel and delete the associated channel
group.
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Configuring Port Channels
Adding a Layer 2 Port to a Port Channel
Command
Purpose
no interface port-channel channel-number
Removes the port channel and deletes the associated
channel group.
This example shows how to create a port channel:
switch# configure terminal
switch (config)# interface port-channel 1
See the “Compatibility Requirements” section for details on how the interface configuration changes when
you delete the port channel.
Adding a Layer 2 Port to a Port Channel
You can add a Layer 2 port to a new channel group or to a channel group that already contains Layer 2 ports.
The software creates the port channel associated with this channel group if the port channel does not already
exist.
Before You Begin
• Enable LACP if you want LACP-based port channels.
• Before you configure this feature for the entire system, ensure that you are in the correct VDC. To change
the VDC, use the switchto vdc command.
• All Layer 2 member ports must run in full-duplex mode and at the same speed.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
port-channel channel-number
Specifies the port-channel interface to configure, and enters
the interface configuration mode. The range is from 1 to 4096.
The Cisco NX-OS software automatically creates the channel
group if it does not already exist.
Step 3
switch(config-if)# switchport
Configures the interface as a Layer 2 access port.
Step 4
switch(config-if)# switchport
mode trunk
(Optional)
Configures the interface as a Layer 2 trunk port.
Step 5
switch(config-if)# switchport
trunk {allowed vlan vlan-id |
native vlan-id}
(Optional)
Configures necessary parameters for a Layer 2 trunk port.
Step 6
switch(config-if)# channel-group Configures the port in a channel group and sets the mode. The
channel-number [force] [mode channel-number range is from 1 to 4096. This command
creates the port channel associated with this channel group if
{on | active | passive}]
the port channel does not already exist. All static port-channel
interfaces are set to mode on. You must set all LACP-enabled
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Configuring Port Channels
Adding a Layer 2 Port to a Port Channel
Command or Action
Purpose
port-channel interfaces to active or passive. The default mode
is on.
Forces an interface with some incompatible configurations to
join the channel. The forced interface must have the same
speed, duplex, and flow control settings as the channel group.
Note
The force option fails if the port has a QoS policy
mismatch with the other members of the port channel.
Step 7
switch(config-if)# show interface (Optional)
Displays interface information.
type slot/port
Step 8
switch(config-if)# show interface (Optional)
Displays the interfaces and VLANs that produce an error
status error policy [detail]
during policy programming to ensure that policies are
consistent with hardware policies.
Use the detail command to display the details of the interfaces
that produce an error.
Step 9
switch(config-if)# no shutdown (Optional)
Clears the errors on the interfaces and VLANs where policies
correspond with hardware policies. This command allows
policy programming to continue and the port to come up. If
policies do not correspond, the errors are placed in an
error-disabled policy state.
Step 10
switch(config-if)# copy
running-config startup-config
(Optional)
Copies the running configuration to the startup configuration.
Use the no channel-group command to remove the port from the channel group.
Table 4: Removing a Port From the Channel Group
Command
Purpose
no channel-group
Removes the port from the channel group.
This example shows how to add a Layer 2 Ethernet interface 1/4 to channel group 5:
switch# configure terminal
switch (config)# interface ethernet 1/4
switch(config-if)# switchport
switch(config-if)# channel-group 5
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Configuring Port Channels
Adding a Layer 3 Port to a Port Channel
Adding a Layer 3 Port to a Port Channel
You can add a Layer 3 port to a new channel group or to a channel group that is already configured with Layer
3 ports. The software creates the port channel associated with this channel group if the port channel does not
already exist.
If the Layer 3 port that you are adding has a configured IP address, the system removes that IP address before
adding the port to the port channel. After you create a Layer 3 port channel, you can assign an IP address to
the port-channel interface. You can also add subinterfaces to an existing Layer 3 port channel.
Before You Begin
• Enable LACP if you want LACP-based port channels.
• Before you configure this feature for the entire system, ensure that you are in the correct VDC. To change
the VDC, use the switchto vdc command.
• Remove any IP addresses configured on the Layer 3 interface.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
port-channel channel-number
Specifies the port-channel interface to configure, and enters the
interface configuration mode. The range is from 1 to 4096. The
Cisco NX-OS software automatically creates the channel group
if it does not already exist.
Step 3
switch(config-if)# no switchport Configures the interface as a Layer 2 access port.
Step 4
switch(config-if)#
channel-group channel-number
[force] [mode {on | active |
passive}]
Configures the port in a channel group and sets the mode. The
channel-number range is from 1 to 4096. This command creates
the port channel associated with this channel group if the port
channel does not already exist. All static port-channel interfaces
are set to mode on. You must set all LACP-enabled port-channel
interfaces to active or passive. The default mode is on.
Forces an interface with some incompatible configurations to
join the channel. The forced interface must have the same speed,
duplex, and flow control settings as the channel group.
Step 5
switch(config-if)# show
interface type slot/port
Step 6
switch(config-if) show interface (Optional)
Displays the interfaces and VLANs that produce an error during
status error policy [detail]
policy programming to ensure that policies are consistent with
hardware policies.
(Optional)
Displays interface information.
Use the detail command to display the details of the interfaces
that produce an error.
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Configuring Port Channels
Configuring the Bandwidth and Delay for Informational Purposes
Command or Action
Purpose
Step 7
switch(config-if) no shutdown (Optional)
Clears the errors on the interfaces and VLANs where policies
correspond with hardware policies. This command allows policy
programming to continue and the port to come up. If policies
do not correspond, the errors are placed in an error-disabled
policy state.
Step 8
switch(config-if) copy
(Optional)
running-config startup-config Copies the running configuration to the startup configuration.
Use the no channel-group command to remove the port from the channel group.
Table 5: Removing a Port From the Channel Group
Command
Purpose
no channel-group
Removes the port from the channel group.
This example shows how to add a Layer 3 Ethernet interface 1/5 to channel group 6 in on mode:
switch# configure terminal
switch (config)# interface ethernet 1/5
switch(config-if)# no switchport
switch(config-if)# channel-group 6
This example shows how to create a Layer 3 port-channel interface and assign the IP address:
switch# configure terminal
switch(config)# interface port-channel 4
switch(config-if)# ip address 192.0.2.1/8
Configuring the Bandwidth and Delay for Informational Purposes
The bandwidth of the port channel is determined by the number of total active links in the channel.
You configure the bandwidth and delay on port-channel interfaces for informational purposes.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
port-channel channel-number
Specifies the port-channel interface to configure, and enters
the interface configuration mode.
Step 3
switch(config-if)# bandwidth value Specifies the bandwidth, which is used for informational
purposes. The range is from 1 to 80,000,000 kbs. The
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Configuring Port Channels
Shutting Down and Restarting the Port-Channel Interface
Command or Action
Purpose
default value depends on the total active interfaces in the
channel group.
Step 4
switch(config-if)# delay value
Specifies the throughput delay, which is used for
informational purposes. The range is from 1 to 16,777,215
tens of microseconds. The default value is 10
microseconds.
Note
Prior to Cisco Release 4.2(1), the default delay
value was 100 microseconds.
Step 5
switch(config-if)# exit
Exits the interface mode and returns to the configuration
mode.
Step 6
switch(config)# show interface
port-channel channel-number
(Optional)
Displays interface information for the specified port
channel.
Step 7
switch(config)# copy
running-config startup-config
(Optional)
Copies the running configuration to the startup
configuration.
This example shows how to configure the informational parameters of the bandwidth and delay for port
channel 5:
switch# configure terminal
switch (config)# interface port-channel 5
switch(config-if)# bandwidth 60000000
switch(config-if)# delay 10000
switch(config-if)#
Shutting Down and Restarting the Port-Channel Interface
You can shut down and restart the port-channel interface. When you shut down a port-channel interface, no
traffic passes and the interface is administratively down.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
port-channel channel-number
Specifies the port-channel interface to configure, and enters
the interface configuration mode.
Step 3
switch(config-if)# shutdown | no Shuts down the interface. No traffic passes and the interface
displays as administratively down. The default is no shutdown.
shutdown
The no shutdown command opens the interface. The interface
displays as administratively up. If there are no operational
problems, traffic passes. The default is no shutdown.
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Configuring Port Channels
Configuring a Port-Channel Description
Command or Action
Purpose
Step 4
switch(config-if)# exit
Exits the interface mode and returns to the configuration mode.
Step 5
switch# show interface
port-channel channel-number
Displays interface information for the specified port channel.
Step 6
switch# show interface status
error policy [detail]
(Optional)
Displays the interfaces and VLANs that produce an error
during policy programming to ensure that policies are
consistent with hardware policies.
Use the detail command to display the details of the interfaces
that produce an error.
Step 7
switch# no shutdown
(Optional)
Clears the errors on the interfaces and VLANs where policies
correspond with hardware policies. This command allows
policy programming to continue and the port to come up. If
policies do not correspond, the errors are placed in an
error-disabled policy state.
Step 8
switch# copy running-config
startup-config
(Optional)
Copies the running configuration to the startup configuration.
This example shows how to bring up the interface for port channel 2:
switch# configure terminal
switch (config)# interface port-channel 2
switch(config-if)# no shutdown
Configuring a Port-Channel Description
You can configure a description for a port channel.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
port-channel channel-number
Specifies the port-channel interface to configure, and enters
the interface configuration mode. The range is from 1 to
4096. The Cisco NX-OS software automatically creates
the channel group if it does not already exist.
Step 3
switch(config-if)# description
Allows you to add a description to the port-channel
interface. You can use up to 80 characters in the
description. By default, the description does not display;
you must configure this parameter before the description
displays in the output.
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Configuring Port Channels
Configuring the Speed and Duplex Settings for a Port-Channel Interface
Command or Action
Purpose
Step 4
switch(config-if)# exit
Exits the interface mode and returns to the configuration
mode.
Step 5
switch(config-if)# show interface (Optional)
Displays interface information for the specified port
port-channel channel-number
channel.
Step 6
switch(config-if)# copy
running-config startup-config
(Optional)
Copies the running configuration to the startup
configuration.
This example shows how to add a description to port channel 2:
switch# configure terminal
switch (config)# interface port-channel 2
switch(config-if)# description engineering
Configuring the Speed and Duplex Settings for a Port-Channel Interface
You can configure the speed and duplex settings for a port-channel interface.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface port-channel Specifies the port-channel interface to configure,
and enters the interface configuration mode.
channel-number
Step 3
switch(config-if)# speed {10 | 100 | 1000 Sets the speed for the port-channel interface. The
default is auto for autonegotiation.
| auto}
Step 4
switch(config-if)# duplex {auto | full | Sets the duplex for the port-channel interface. The
default is auto for autonegotiation.
half}
Step 5
switch(config-if)# exit
Exits the interface mode and returns to the
configuration mode.
Step 6
switch# show interface port-channel
channel-number
(Optional)
Displays interface information for the specified port
channel.
Step 7
switch# copy running-config
startup-config
(Optional)
Copies the running configuration to the startup
configuration.
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Configuring Port Channels
Configuring Flow Control
This example shows how to set port channel 2 to 100 Mb/s:
switch# configure terminal
switch (config)# interface port-channel 2
switch(config-if)# speed 100
Configuring Flow Control
You can enable or disable the capability of the port-channel interfaces that run at 1 Gb or higher to send or
receive flow-control pause packets. For port-channel interfaces that run at lower speeds, you can enable or
disable only the capability of the port-channel interfaces to receive pause packets.
Note
The settings have to match at both the local and remote ends of the link so that flow control can work
properly.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface port-channel Specifies the port-channel interface to configure, and
enters the interface configuration mode.
channel-number
Step 3
switch(config-if)# flowcontrol {receive Sets the flow control parameters for sending and
receiving the pause packets for the port-channel
| send} {desired | off | on}
interface. The default is desired.
Step 4
switch(config-if)# exit
Exits the interface mode and returns to the
configuration mode.
Step 5
switch# show interface port-channel
channel-number
(Optional)
Displays interface information for the specified port
channel.
Step 6
switch# copy running-config
startup-config
(Optional)
Copies the running configuration to the startup
configuration.
This example shows how to configure the port-channel interface for port channel group 2 to send and receive
pause packets:
switch# configure terminal
switch(config)# interface port-channel 2
switch(config-if)# flowcontrol receive on
switch(config-if)# flowcontrol send on
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Configuring Port Channels
Configuring Load Balancing Using Port Channels
Configuring Load Balancing Using Port Channels
You can configure the load-balancing algorithm for port channels that applies to the entire device or to only
one module regardless of the VDC association. Module-based load balancing takes precedence over
device-based load balancing.
Before You Begin
• Enable LACP if you want LACP-based port channels.
• Before you configure this feature for the entire system, ensure that you are in the correct VDC. To change
the VDC, use the switchto vdc command.
Procedure
Command or Action
Purpose
Step 1 switch# configure terminal
Enters global configuration mode.
Step 2 switch(config)# [no]
port-channel load-balance
method {dst ip | dst
ip-l4port-vlan | dst ip-vlan | dst
mac | dst l4port | dst ip-l4port
| src-dst ip | src-dst mac |
src-dst l4port | src-dst
ip-l4port | src-dst ip-vlan |
src-dst ip-l4port-vlan | src ip |
src ip-l4port-vlan | src
ip-l4port | src ip-vlan | src mac
| src l4port | hash-modulo
[force]} [gtp-teid] [module
module-number | fex {fex-range
| all}] [asymmetric] [rotate
rotate]
Specifies the load-balancing algorithm for the device or module. The
range depends on the device. The default for Layer 3 is src-dst ip
for both IPv4 and IPv6, and the default for non-IP is src-dst mac.
The asymmetric keyword is valid with the src-dst ip
command and F2 or F2e modules only. As F2 or F2e
modules are symmetric by default, the asymmetric keyword
prevents a traffic-drop occurring during bi-directional flow.
A warning message prompts you that an F2 or F2e module
needs to be enabled. This improves load-balancing and
avoids any disruption to the system.
Use the no port-channel load-balance src-dst mac asymmetric
command to revert back to the default system settings (symmetrical).
Note
If a module-based configuration already exists, it takes
precedence over the default system settings.
Use the no port-channel load-balance src-dst mac asymmetric
module command at module level to revert back to system level
settings (symmetrical).
Note
The module, asymmetric, and rotate keywords are invalid
with the hash-modulo command.
When the gtp-teid keyword is specified in a packet that includes a
GTP header field, the port-channel member selected depends not
only on the already specified packet header fields such as MAC
address, IP address, and L4 ports, but also on the 32-bit Tunnel
Endpoint Identifier (TEID) header field. The packet must enter a port
on an M3 module for the TEID header field to be used in the
port-channel load-balancing.
Note
When the gtp-teid keyword is specified in a packet, the packet's
TEID header field is used in port-channel member selection only if
the packet contains an IPv4 or IPv6 header field followed by a UDP
header field with the destination port 2152 and a GTP version 1
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Configuring Port Channels
Configuring Load Balancing Using Port Channels
Command or Action
Purpose
header field with the Protocol Type 1. All the other GTP header fields
are considered GTP control messages. To avoid reordering of the
GTP control messages in the network between GTP endpoints,
NX-OS does not include the TEID header fields of the GTP control
messages in its channel member selection.
Note
The gtp-teid keyword is supported only on M3 modules
and does not affect the behavior of the other modules.
Step 3 show port-channel
load-balance
(Optional)
Displays the port-channel load-balancing algorithm.
Step 4 switch# copy running-config
startup-config
(Optional)
Copies the running configuration to the startup configuration.
Use the no port-channel load-balance to restore the default load-balancing algorithm of src-dst mac for
non-IP traffic and src-dst ip for IP traffic.
Command
Purpose
no port-channel load-balance
Restores the default load-balancing algorithm.
This example shows how to configure source IP load balancing for port channels on module 5:
switch# configure terminal
switch(config)# port-channel load-balance src-ip-l4port module 5
This example shows how to configure different combinations for symmetric port channel load balancing for
a port channel connected to switch1 and switch2. Use the same rotate rotate-value as listed in the following
configuration combinations.
! Configure port-channel hash distribution at the global level!
switch1(config)# port-channel hash-distribution fixed
Switch2(config)# port-channel hash-distribution fixed
! Configure symmetric port-channel load balancing combinations on both
switch1 and switch2 of a port channel.!
!Combination 1!
switch1(config)# port-channel load-balance src ip
Switch2(config)# port-channel load-balance dst ip rotate 4
!Combination 2!
switch1(config)# port-channel load-balance dst ip
Switch2(config)# port-channel load-balance src ip rotate 4
!Combination 3!
switch1(config)# port-channel load-balance src ip-l4port
Switch2(config)# port-channel load-balance dst ip-l4port rotate 6
!Combination 4!
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Configuring Port Channels
Enabling LACP
switch1(config)# port-channel load-balance dst ip-l4port
Switch2(config)# port-channel load-balance src ip-l4port rotate 6
!Combination 5!
switch1(config)# port-channel load-balance src ip-l4port vlan
Switch2(config)# port-channel load-balance dst ip-l4port rotate 8
!Combination 6!
switch1(config)# port-channel load-balance dst ip-l4port vlan
Switch2(config)# port-channel load-balance src ip-l4port rotate 8
!Combination 7!
switch1(config)# port-channel load-balance src ip-vlan
Switch2(config)# port-channel load-balance dst ip-vlan rotate 8
!Combination 8!
switch1(config)# port-channel load-balance dst ip-vlan
Switch2(config)# port-channel load-balance src ip-vlan rotate 8
!Combination 9!
switch1(config)# port-channel load-balance src l4port
Switch2(config)# port-channel load-balance dst l4port rotate 2
!Combination 10!
switch1(config)# port-channel load-balance dst l4port
Switch2(config)# port-channel load-balance src l4port rotate 2
!Combination 11!
switch1(config)# port-channel load-balance src mac
Switch2(config)# port-channel load-balance dst mac rotate 6
!Combination 12!
switch1(config)# port-channel load-balance dst mac
Switch2(config)# port-channel load-balance src mac rotate 6
Enabling LACP
LACP is disabled by default; you must enable LACP before you begin LACP configuration. You cannot
disable LACP while any LACP configuration is present.
LACP learns the capabilities of LAN port groups dynamically and informs the other LAN ports. Once LACP
identifies correctly matched Ethernet links, it group the links into a port channel. The port channel is then
added to the spanning tree as a single bridge port.
To configure LACP, you must do the following:
• Enable LACP globally by using the feature lacp command.
• You can use different modes for different interfaces within the same LACP-enabled port channel.
• You can change the mode between active and passive for an interface only if it is the only interface that
is designated to the specified channel group.
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Configuring Port Channels
Configuring LACP Port-Channel Port Modes
Before You Begin
Before you configure this feature for the entire system, ensure that you are in the correct VDC. To change the
VDC, use the switchto vdc command.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# feature lacp
Enables LACP on the device.
Step 3
switch(config)# copy running-config
startup-config
(Optional)
Copies the running configuration to the startup
configuration.
This example shows how to enable LACP:
switch# configure terminal
switch(config)# feature lacp
Configuring LACP Port-Channel Port Modes
After you enable LACP, you can configure the channel mode for each individual link in the LACP port channel
as active or passive. This channel configuration mode allows the link to operate with LACP.
When you configure port channels with no associated aggregation protocol, all interfaces on both sides of the
link remain in the on channel mode.
Before You Begin
Before you configure this feature for the entire system, ensure that you are in the correct VDC. To change the
VDC, use the switchto vdc command.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
port-channel channel-number
Specifies the port-channel interface to configure, and
enters the interface configuration mode.
Step 3
switch(config-if)# channel-group
Specifies the port mode for the link in a port channel.
number mode {active | on | passive} After LACP is enabled, you configure each link or the
entire channel as active or passive.
When you run port channels with no associated
aggregation protocol, the port-channel mode is always
on.
The default port-channel mode is on.
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Configuring Port Channels
Configuring LACP Port-Channel Minimum Links
Command or Action
Purpose
Step 4
switch(config-if)# show port-channel (Optional)
Displays summary information about the port channels.
summary
Step 5
switch(config-if)# copy
running-config startup-config
(Optional)
Copies the running configuration to the startup
configuration.
This example shows how to set the LACP-enabled interface to the active port-channel mode for Ethernet
interface 1/4 in channel group 5:
switch# configure terminal
switch(config)# interface ethernet 1/4
switch(config-if)# channel-group 5 mode active
Configuring LACP Port-Channel Minimum Links
From Cisco NX-OS Release 5.1, you can configure the LACP minimum links feature. Although minimum
links and maxbundles work only in LACP, you can enter the commands for these features for non-LACP port
channels, but these commands are nonoperational.
Before You Begin
Ensure that you are in the correct port-channel interface.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface port-channel Specifies the port-channel interface to configure, and
enters the interface configuration mode.
channel-number
Step 3
switch(config-if)# lacp min-links
number
Step 4
switch(config-if)# show running-config (Optional)
Displays the port-channel minimum links
interface port-channel number
configuration.
Specifies the port-channel interface to configure the
number of minimum links and enters the interface
configuration mode. The range is from 1 to 16.
Use the no lacp min-links command to restore the default port-channel minimum links configuration.
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Configuring Port Channels
Configuring the LACP Port-Channel MaxBundle
Table 6: Restoring the Default Port-Channel Minimum Links Configuration
Command
Purpose
no lacp min-links
Restores the default port-channel minimum links
configuration.
This example shows how to configure the minimum number of port-channel interfaces on module 3:
switch# configure terminal
switch(config)# lacp min-links 3
Configuring the LACP Port-Channel MaxBundle
From Cisco NX-OS Release 5.1, you can configure the LACP maxbundle feature. Although minimum links
and maxbundles work only in LACP, you can enter the commands for these features for non-LACP port
channels, but these commands are nonoperational.
Before You Begin
Ensure that you are in the correct port-channel interface.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
port-channel channel-number
Specifies the port-channel interface to configure, and enters
the interface configuration mode.
Step 3
switch(config-if)# lacp
max-bundle number
Specifies the port-channel interface to configure max-bundle,
and enters the interface configuration mode.
The default value for the port-channel max-bundle is 16.
The allowed range is from 1 to 16.
Note
Step 4
switch(config-if)# show
running-config interface
port-channel number
Even if the default value is 16, the number of active
members in a port channel is the minimum of the
pc_max_links_config and pc_max_active_members
that is allowed in the port channel.
(Optional)
Displays the port-channel minimum links configuration.
Use the no lacp max-bundle command to restore the default port-channel max-bundle configuration.
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Configuring Port Channels
Configuring the LACP Fast Timer Rate
Table 7: Restoring the Default Port-Channel Max-Bundle Configuration
Command
Purpose
no lacp max-bundle
Restores the default port-channel max-bundle
configuration.
This example shows how to configure the port channel interface max-bundle on module 3:
switch# configure terminal
switch(config)# lacp max-bundle 3
Configuring the LACP Fast Timer Rate
You can change the LACP timer rate to modify the duration of the LACP timeout. Use the lacp rate command
to set the rate at which LACP control packets are sent to an LACP-supported interface. You can change the
timeout rate from the default rate (30 seconds) to the fast rate (1 second). This command is supported only
on LACP-enabled interfaces.
Note
We do not recommend changing the LACP timer rate. In-service software upgrade (ISSU) and stateful
switchover (SSO) are not supported with the LACP fast rate timer.
Before You Begin
• Ensure that you have enabled the LACP feature.
• Before you configure this feature for the entire system, ensure that you are in the correct VDC. To change
the VDC, use the switchto vdc command.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
port-channel channel-number
Specifies the port-channel interface to configure, and
enters the interface configuration mode.
Step 3
switch(config-if)# lacp rate fast
Configures the fast rate (one second) at which LACP
control packets are sent to an LACP-supported interface.
To reset the timeout rate to its default, use the no form
of the command.
This example shows how to configure the LACP fast rate on Ethernet interface 1/4:
switch# configure terminal
switch(config)# interface ethernet 1/4
switch(config-if)# lacp rate fast
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Configuring Port Channels
Configuring the LACP System Priority
This example shows how to restore the LACP default rate (30 seconds) on Ethernet interface 1/4:
switch# configure terminal
switch(config)# interface ethernet 1/4
switch(config-if)# no lacp rate fast
Configuring the LACP System Priority
The LACP system ID is the combination of the LACP system priority value and the MAC address.
You can reuse the same configuration for the system priority values in more than one VDC.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# lacp system-priority Configures the system priority for use with LACP. Valid
values are from 1 through 65535, and higher numbers
priority
have a lower priority. The default value is 32768.
Note
Each VDC has a different LACP system ID
because the software adds the MAC address to
this configured value.
Step 3
switch(config)# show lacp
system-identifier
Step 4
switch(config)# show running-config (Optional)
Displays the port-channel minimum links configuration.
interface port-channel number
(Optional)
Displays the LACP system identifier.
This example shows how to set the LACP system priority to 2500:
switch# configure terminal
switch(config)# lacp system-priority 2500
Configuring the LACP Port Priority
When you enable LACP, you can configure each link in the LACP port channel for the port priority.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface port-channel Specifies the port-channel interface to configure, and
enters the interface configuration mode.
channel-number
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Configuring Port Channels
Disabling LACP Graceful Convergence
Command or Action
Purpose
Step 3
switch(config-if)# lacp port-priority
priority
Configures the port priority for use with LACP. Valid
values are from1 through 65535, and higher numbers
have a lower priority. The default value is 32768.
Step 4
switch(config-if)# show running-config (Optional)
Displays the port-channel minimum links
interface port-channel number
configuration.
This example shows how to set the LACP port priority for Ethernet interface 1/4 to 40000:
switch# configure terminal
switch(config)# interface ethernet 1/4
switch(config-if)# lacp port-priority 40000
Disabling LACP Graceful Convergence
By default, LACP graceful convergence is enabled. In situations where you need to support LACP
interoperability with devices where the graceful failover defaults may delay the time taken for a disabled port
to be brought down or cause traffic from the peer to be lost, you can disable convergence. If the downstream
access switch is not a Cisco Nexus device, disable the LACP graceful convergence option.
Note
The port channel has to be in the administratively down state before the command can be run.
Before You Begin
• Before you configure this feature for the entire system, ensure that you are in the correct VDC. To change
the VDC, use the switchto vdc command.
• Enable LACP.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface port-channel Specifies the port-channel interface to configure,
and enters the interface configuration mode.
channel-number
Step 3
switch(config-if)# shutdown
Administratively shuts down the port channel.
Step 4
switch(config-if)# no lacp
graceful-convergence
Disables LACP graceful convergence on the port
channel.
Step 5
switch(config-if)# no shutdown
Brings the port channel administratively up.
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Configuring Port Channels
Disabling LACP Port
Command or Action
Step 6
Purpose
switch(config-if)# copy running-config (Optional)
Copies the running configuration to the startup
startup-config
configuration.
This example shows how to disable LACP graceful convergence on a port channel:
switch# configure terminal
switch(config)# interface port-channel 1
switch(config-if)# shutdown
switch(config-if)# no lacp graceful-convergence
switch(config-if)# no shutdown
Re-Enabling LACP Graceful Convergence
If the default LACP graceful convergence is once again required, you can re-enable convergence.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface port-channel Specifies the port-channel interface to configure,
and enters the interface configuration mode.
channel-number
Step 3
switch(config-if)# shutdown
Administratively shuts down the port channel.
Step 4
switch(config-if)# lacp
graceful-convergence
Enables LACP graceful convergence on the port
channel.
Step 5
switch(config-if)# no shutdown
Brings the port channel administratively up.
Step 6
switch(config-if)# copy running-config (Optional)
Copies the running configuration to the startup
startup-config
configuration.
This example shows how to enable LACP graceful convergence on a port channel:
switch# configure terminal
switch(config)# interface port-channel 1
switch(config-if)# shutdown
switch(config-if)# lacp graceful-convergence
switch(config-if)# no shutdown
Disabling LACP Port
LACP sets a port to the suspended state if it does not receive an LACP PDU from the peer. This process can
cause some servers to fail to boot up as they require LACP to logically bring up the port.
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Configuring Port Channels
Disabling LACP Port
Note
You should only enter the lacp suspend-individual command on edge ports. The port channel has to be
in the administratively down state before you can use this command.
Before You Begin
• Before you configure this feature for the entire system, ensure that you are in the correct VDC. To change
the VDC, use the switchto vdc command.
• Enable LACP.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface port-channel Specifies the port-channel interface to configure,
and enters the interface configuration mode.
channel-number
Step 3
switch(config-if)# shutdown
Administratively shuts down the port channel.
Step 4
switch(config-if)# no lacp
suspend-individual
Disables LACP individual port suspension
behavior on the port channel.
Step 5
switch(config-if)# no shutdown
Brings the port channel administratively up.
Step 6
switch(config-if)# copy running-config (Optional)
Copies the running configuration to the startup
startup-config
configuration.
This example shows how to disable LACP individual port suspension on a port channel:
switch# configure terminal
switch(config)# interface port-channel 1
switch(config-if)# shutdown
switch(config-if)# no lacp suspend-individual
switch(config-if)# no shutdown
Re-Enabling LACP Port
You can re-enable the default LACP individual port suspension.
Procedure
Step 1
Command or Action
Purpose
switch# configure terminal
Enters global configuration mode.
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Configuring Port Channels
Configuring Port-Channel Hash Distribution
Command or Action
Purpose
Step 2
switch(config)# interface port-channel Specifies the port-channel interface to configure,
and enters the interface configuration mode.
channel-number
Step 3
switch(config-if)# shutdown
Administratively shuts down the port channel.
Step 4
switch(config-if)# lacp
suspend-individual
Enables LACP individual port suspension behavior
on the port channel.
Step 5
switch(config-if)# no shutdown
Brings the port channel administratively up.
Step 6
switch(config-if)# copy running-config (Optional)
Copies the running configuration to the startup
startup-config
configuration.
This example shows how to re-enable the LACP individual port suspension on a port channel:
switch# configure terminal
switch(config)# interface port-channel 1
switch(config-if)# shutdown
switch(config-if)# lacp suspend-individual
switch(config-if)# no shutdown
Configuring Port-Channel Hash Distribution
From Cisco NX-OS Release 6.1(1), the adaptive and fixed hash distribution configuration is supported at both
global and port-channel levels. This option minimizes traffic disruption by minimizing Result Bundle Hash
(RBH) distribution changes when members come up or go down so that flows that are mapped to unchange
RBH values continue to flow through the same links. The port-channel level configuration overrules the global
configuration. The default configuration is adaptive globally, and there is no configuration for each port
channel, so there is no change during an ISSU. No ports are flapped when the command is applied, and the
configuration takes effect at the next member link change event. Both modes work with RBH module or
non-module schemes.
During an ISSD to a lower version that does not support this feature, you must disable this feature if the fixed
mode command is being used globally or if there is a port-channel level configuration.
From Cisco Nexus Release 8.(0)1, symmetric hashing is supported on M3 modules.
Configuring Port-Channel Hash Distribution at the Global Level
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# port-channel Specifies the port-channel hash distribution at the global level.
hash-distribution {adaptive |
fixed}
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Configuring Port Channels
Configuring Port-Channel Hash Distribution
Command or Action
Purpose
• adaptive—This is the default mode. RBH values are
asymmetric.
• fixed—Peer port connections must be in an ascending order.
RBH values are distributed symmetrically as per the
ascending order of the port. The number of buckets in each
port is equal.
While configuring this command, the following warning is
displayed:
This global command does not take effect until the next member
link event (link down/up/no shutdown/shutdown). Do you still
want to continue(y/n)? [yes]
Step 3
switch(config)# copy
(Optional)
running-config startup-config Copies the running configuration to the startup configuration.
This example shows how to configure adaptive hash distribution at the global level:
configure terminal
port-channel hash-distribution adaptive
show port-channel rbh-distribution
ChanId
Member port
RBH values
-------- ------------- ----------------3022
Eth15/5
0
3022
Eth15/21
4
3022
Eth15/6
1
3022
Eth15/13
2
3022
Eth15/14
3
Num of buckets
---------------1
1
1
1
1
Configuring Port-Channel Hash Distribution at the Port-Channel Level
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface
Specifies the interface to configure, and enters the interface
port-channel {channel-number | configuration mode.
range}
Step 3
switch(config-if)# [no]
Specifies the port-channel hash distribution at the global level.
port-channel hash-distribution
• adaptive—This is the default mode. RBH values are
{adaptive | fixed}
asymmetric.
• fixed—Peer port connections must be in an ascending
order. RBH values are distributed symmetrically as per
the ascending order of the port. The number of buckets
in each port is equal.
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Configuring Port Channels
Configuring RBH Modulo Mode
Command or Action
Purpose
While configuring this command, the following warning is
displayed:
The command does not take effect until the next member link
event (link down/up/no shutdown/shutdown). Do you still
want to continue(y/n)? [yes]
Step 4
switch(config-if)# copy
running-config startup-config
(Optional)
Copies the running configuration to the startup configuration.
This example shows how to configure fixed hash distribution at the port channel level:
configure terminal
interface port-channel 3010
port-channel hash-distribution fixed
show port-channel rbh-distribution interface port-channel 3021
ChanId
Member port
RBH values
Num of buckets
-------- ------------- ----------------- ---------------3021
Eth15/23
0
1
3021
Eth15/24
1
1
3021
Eth15/25
2
1
3021
Eth15/26
3
1
Configuring RBH Modulo Mode
Enabling RBH modulo mode flaps all port channels.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# port-channel
load-balance hash-modulo
Enables the RBH modulo mode. This command reinitializes
all port channels so there is an option to continue or not
continue.
Note
Step 3
switch(config-if)# copy
running-config startup-config
This command is rejected if the current system-wide
module types include the M1-Series module. To
remove the M1-Series module type from the
system-wide configuration, enter the system
module-type f1, f2, m1xl, m2xl command.
(Optional)
Copies the running configuration to the startup configuration.
This example shows how to enable the RBH modulo mode:
switch# configure terminal
switch(config)# port-channel load-balance hash-modulo
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Configuring Port Channels
Configuring Minimum Links on the FEX Fabric Port Channel
Configuring Minimum Links on the FEX Fabric Port Channel
From Cisco NX-OS Release 6.1(3), you can configure a minimum number of links for the FEX fabric port
channel so that when a certain number of FEX fabric port-channel member ports go down, the host-facing
interfaces of the FEX are suspended.
Before You Begin
Ensure that you are in the correct port-channel interface.
Procedure
Command or Action
Purpose
Step 1
switch# configure terminal
Enters global configuration mode.
Step 2
switch(config)# interface port-channel Specifies the interface to configure and enters the
interface configuration mode.
number
Step 3
switch(config-if)# switchport
Configures the interface as a Layer 2 access port.
Step 4
switch(config-if)# switchport mode
fex-fabric
Sets the port channel to support an external Fabric
Extender.
Step 5
switch(config-if)# [no] port-channel
min-links number
Configures the minimum number of links on the
FEX fabric port channel. The range is from 1 to
16.
Step 6
switch(config-if)# show port-channel
summary
(Optional)
Displays summary information about the port
channels.
Step 7
switch(config-if)# copy running-config (Optional)
Copies the running configuration to the startup
startup-config
configuration.
This example shows how to configure the minimum number of links for the FEX fabric port channel:
switch# configure terminal
switch(config)# interface port-channel 100
switch(config-if)# switchport
switch(config-if)# switchport mode fex-fabric
switch(config-if)# port-channel min-links 3
switch(config-if)# show port-channel summary
Flags: D - Down P - Up in port-channel (members) I - Individual
H - Hot-standby (LACP only) s - Suspended r - Module-removed
S - Switched R - Routed U - Up (port-channel)
M - Not in use. Min-links not met
-------------------------------------------------------------------------------Group Port- Type Protocol Member Ports Channel
-------------------------------------------------------------------------------101 Po101(SM) Eth NONE Eth10/46(P) Eth10/47(P) Eth10/48(P)
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Configuring Port Channels
Configuring Random Load Balance
Configuring Random Load Balance
Configuring Random Load Balance on a Port Channel
Procedure
Step 1
Enter global configuration mode:
switch# configure terminal
Step 2
Configure interface port-channel.
switch(config)# interface port-channel port-channel-number
Step 3
Configure random load balance for the port-channel interface. Use the no form of the following command to
disable the random load balance feature.
switch(config-if)# egress port-channel load-balance random
Note
This will override the default system or module-wide port-channel load balance settings. To configure
random load balancing for ingress traffic, configure the egress port-channel load-balance random
command on an switch virtual interface (SVI) on Layer 3.
Configuring Random Load Balance on an Interface
Procedure
Step 1
Enter global configuration mode:
switch# configure terminal
Step 2
Configure a port-channel interface:
switch(config)# interface interface-name
Step 3
Configure random load balance for the interface. Use the no form of the following command to disable the
random load balance feature.
switch(config-if)# egress port-channel load-balance random
Note
The ingress Layer 3 interface or a port-channel interface performs random load balance on the Layer
2 or Layer 3 egress interface and port-channel interface.
Configuring random load balance on a single physical interface is useful in scenarios where traffic
comes in from an ingress Layer 3 interface and goes out of a port-channel interface.
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Configuring Port Channels
Configuring Random Load Balance for a VLAN
Configuring Random Load Balance for a VLAN
Procedure
Step 1
Enter global configuration mode:
switch# configure terminal
Step 2
Configure a VLAN:
switch(config)# vlan vlan-id
Step 3
Enter VLAN configuration mode:
switch(config-vlan)# vlan configuration vlan-id
Step 4
Configure random load balance for the VLAN. Use the no form of the following command to disable the
random load balance feature.
switch(config-if)# egress port-channel load-balance random
Note
Random load balance is applied on all the Layer 2 ingress interfaces under the VLAN. The ingress
interfaces perform random load balance on all the Layer 2 or Layer 3 port-channel egress interfaces.
Configuring Random Load Balance for an SVI
Procedure
Step 1
Enter global configuration mode:
switch# configure terminal
Step 2
Configure a switch virtual interface (SVI):
switch(config)# vlan vlan-range
Step 3
Enter VLAN configuration mode:
switch(config)# vlan configuration vlan-range
Step 4
Configure random load balance for the SVI for ingress traffic. Use the no form of the following command to
disable the random load balance feature.
switch(config-vlan-config)# egress port-channel load-balance random
Example: Configuring Random Load Balance
This example shows how to configure random load balance on a port-channel interface:
configure terminal
interface port-channel 44
egress port-channel load-balance random
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Configuring Port Channels
Verifying Port-Channel Configurations
This example shows how to configure random load balance on a physical interface:
configure terminal
interface Ethernet6/1
egress port-channel load-balance random
This example shows how to configure random load balance on a VLAN:
configure terminal
vlan 100
vlan configuration 100
egress port-channel load-balance random
This example shows how to configure random load balance on a switch virtual interface (SVI) for ingress
traffic:
configure terminal
vlan 2-10
vlan configuration 2-10
egress port-channel load-balance random
Verifying Port-Channel Configurations
Use the following commands to verify port-channel configurations:
Table 8: Verifying Port-Channel Configurations
Command
Purpose
show interface port-channel channel-number
Displays the status of a port-channel interface.
show feature
Displays enabled features.
load-interval {interval seconds {1 | 2 | 3}}
From Cisco NX-OS Release 4.2(1) for the Cisco
Nexus 7000 Series devices, sets three different
sampling intervals to bit-rate and packet-rate statistics.
show port-channel compatibility-parameters
Displays the parameters that must be the same among
the member ports in order to join a port channel.
show port-channel database [interface
port-channel channel-number]
Displays the aggregation state for one or more
port-channel interfaces.
show port-channel load-balance
Displays the type of load balancing in use for port
channels.
show port-channel rbh distribution
Displays the distribution of RBH values across
port-channel interfaces.
show port-channel summary
Displays a summary for the port-channel interfaces.
show port-channel traffic
Displays the traffic statistics for port channels.
show port-channel usage
Displays the range of used and unused channel
numbers.
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Configuring Port Channels
Monitoring the Port-Channel Interface Configuration
Command
Purpose
show lacp {counters [interface port-channel
channel-number] | [interface type/slot] | neighbor
[interface port-channel channel-number] |
port-channel [interface port-channel
channel-number] | system-identifier]]}
Displays information about LACP.
show running-config interface port-channel
channel-number
Displays information about the running configuration
of the port-channel.
show interface status error policy [detail]
Displays errors on interfaces and VLANs that are
inconsistent with hardware policies.
The detail command displays the details of the
interfaces and VLANs that receive an error.
For more information about these commands, see the Cisco Nexus 7000 Series NX-OS Interfaces Command
Reference.
Monitoring the Port-Channel Interface Configuration
Use the following commands to display port-channel interface configurations:
Table 9: Monitoring the Port-Channel Interface Configuration
Command
Purpose
clear counters interface port-channel
channel-number
Clears the counters.
clear lacp counters [interface port-channel
channel-number]
Clears the LACP counters.
load-interval {interval seconds {1 | 2 | 3}}
From Cisco NX-OS Release 4.2(1) for the Cisco
Nexus 7000 Series devices, sets three different
sampling intervals to bit-rate and packet-rate statistics.
show interface counters [module module]
Displays input and output octets unicast packets,
multicast packets, and broadcast packets.
show interface counters detailed [all]
Displays input packets, bytes, and multicast and
output packets and bytes.
show interface counters errors [module module]
Displays information about the number of error
packets.
show lacp counters
Displays statistics for LACP.
Cisco Nexus 7000 Series NX-OS Interfaces Configuration Guide
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Configuring Port Channels
Configuration Examples for Port Channels
See the Cisco Nexus 7000 Series NX-OS Interfaces Command Reference for information about these
commands.
Configuration Examples for Port Channels
This example shows how to create an LACP port channel and add two Layer 2 interfaces to that port channel:
switch# configure terminal
switch(config)# feature lacp
switch(config)# interface port-channel 5
switch(config-if)# interface ethernet 1/4
switch(config-if)# switchport
switch(config-if)# channel-group 5 mode active
switch(config-if)# lacp port priority 40000
switch(config-if)# interface ethernet 1/7
switch(config-if)# switchport
switch(config-if)# channel-group 5 mode
This example shows how to add two Layer 3 interfaces to a channel group. The Cisco NX-OS software
automatically creates the port channel.
switch# configure terminal
switch(config)# interface ethernet 1/5
switch(config-if)# no switchport
switch(config-if)# no ip address
switch(config-if)# channel-group 6 mode active
switch(config)# interface ethernet 2/5
switch(config-if)# no switchport
switch(config-if)# no ip address
switch(config-if)# channel-group 6 mode active
switch(config)# interface port-channel 6
switch(config-if)# ip address 192.0.2.1/8
Related Documents
Table 10: Related Documents
Related Topic
Cisco Nexus 7000 Series NX-OS Interfaces Command Reference
Interfaces Configuration Guide, Cisco DCNM for LAN
Cisco Nexus 7000 Series NX-OS System Management Configuration GuideCisco Nexus 7000 Series NX-OS
System Management Configuration Guide
Cisco Nexus 7000 Series NX-OS High Availability and Redundancy Guide
Cisco Nexus 2000 Series NX-OS Fabric Extender Software Configuration Guide for Cisco Nexus 7000
Series Switches, Release 6.x
Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration GuideCisco Nexus 7000 Series
NX-OS Virtual Device Context Configuration Guide
Cisco Nexus 7000 Series NX-OS Interfaces Configuration Guide
47
Configuring Port Channels
Standards
Related Topic
Cisco NX-OS Licensing Guide
VLANs, MAC address tables, private VLANs, and the Spanning Tree Protocol.
Cisco Nexus 7000 Series NX-OS Layer 2 Switching Configuration GuideCisco Nexus 7000 Series NX-OS
Layer 2 Switching Configuration Guide
Cisco Nexus 7000 Series NX-OS FabricPath Command Reference
Cisco Nexus 7000 Series NX-OS FabricPath Configuration Guide
Cisco Nexus 7000 Series NX-OS Release NotesCisco Nexus 7000 Series NX-OS Release Notes
Standards
Table 11: Standards
Standards
Title
IEEE 802.3ad
—
MIBs
Table 12: MIBs
MIBs
• IEEE8023-LAG-CAPABILITY
• CISCO-LAG-MIB
Cisco Nexus 7000 Series NX-OS Interfaces Configuration Guide
48
MIBs Link
To locate and download MIBs, go to:
http://www.cisco.com/public/sw-center/netmgmt/cmtk/
mibs.shtml
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