Cisco Nexus 7000 NX-OS networking Configuration guide

S e n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
CH A P T E R
819
2.0
Configuring EIGRP
This chapter describes how to configure the Enhanced Interior Gateway Routing Protocol (EIGRP) on
the Cisco NX-OS device.
This chapter includes the following sections:
•
Information About EIGRP, page 8-1
•
Licensing Requirements for EIGRP, page 8-8
•
Prerequisites for EIGRP, page 8-8
•
Configuration Guidelines and Limitations, page 8-9
•
Configuring Basic EIGRP, page 8-9
•
Configuring Advanced EIGRP, page 8-14
•
Configuring Virtualization for EIGRP, page 8-28
•
Verifying EIGRP Configuration, page 8-30
•
Displaying EIGRP Statistics, page 8-30
•
EIGRP Example Configuration, page 8-30
•
Related Topics, page 8-31
•
Default Settings, page 8-31
•
Additional References, page 8-31
•
Feature History for EIGRP, page 8-32
Information About EIGRP
EIGRP combines the benefits of distance vector protocols with the features of link-state protocols.
EIGRP sends out periodic Hello messages for neighbor discovery. Once EIGRP learns a new neighbor,
it sends a one-time update of all the local EIGRP routes and route metrics. The receiving EIGRP router
calculates the route distance based on the received metrics and the locally assigned cost of the link to
that neighbor. After this initial full route table update, EIGRP sends incremental updates to only those
neighbors affected by the route change. This process speeds convergence and minimizes the bandwidth
used by EIGRP.
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Configuring EIGRP
Information About EIGRP
Se n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
This section includes the following topics:
•
EIGRP Components, page 8-2
•
EIGRP Route Updates, page 8-3
•
Advanced EIGRP, page 8-4
EIGRP Components
EIGRP has the following basic components:
•
Reliable Transport Protocol, page 8-2
•
Neighbor Discovery and Recovery, page 8-2
•
Diffusing Update Algorithm, page 8-3
Reliable Transport Protocol
The Reliable Transport Protocol guarantees ordered delivery of EIGRP packets to all neighbors. (See
the “Neighbor Discovery and Recovery” section on page 8-2.) The Reliable Transport Protocol supports
an intermixed transmission of multicast and unicast packets. The reliable transport can send multicast
packets quickly when unacknowledged packets are pending. This provision helps to ensure that the
convergence time remains low for various speed links. See the “Configuring Advanced EIGRP” section
on page 8-14 for details about modifying the default timers that control the multicast and unicast packet
transmissions.
The Reliable Transport Protocol includes the following message types:
•
Hello—Used for neighbor discovery and recovery. By default, EIGRP sends a periodic multicast
Hello message on the local network at the configured hello interval. By default, the hello interval is
5 seconds.
•
Acknowledgement—Verify reliable reception of Updates, Queries, and Replies.
•
Updates—Send to affected neighbors when routing information changes. Updates include the route
destination, address mask, and route metrics such as delay and bandwidth. The update information
is stored in the EIGRP topology table.
•
Queries and Replies—Sent as necessary as part of the Diffusing Update Algorithm used by EIGRP.
Neighbor Discovery and Recovery
EIGRP uses the Hello messages from the Reliable Transport Protocol to discover neighboring EIGRP
routers on directly attached networks. EIGRP adds neighbors to the neighbor table. The information in
the neighbor table includes the neighbor address, the interface it was learned on, and the hold time, which
indicates how long EIGRP should wait before declaring a neighbor unreachable. By default, the hold
time is three times the hello interval or 15 seconds.
EIGRP sends a series of Update messages to new neighbors to share the local EIGRP routing
information. This route information is stored in the EIGRP topology table. After this initial transmission
of the full EIGRP route information, EIGRP sends Update messages only when a routing change occurs.
These Update messages contain only the new or changed information and are sent only to the neighbors
affected by the change. See the “EIGRP Route Updates” section on page 8-3.
EIGRP also uses the Hello messages as a keepalive to its neighbors. As long as Hello messages are
received, Cisco NX-OS can determine that a neighbor is alive and functioning.
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Information About EIGRP
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Diffusing Update Algorithm
The Diffusing Update Algorithm (DUAL) calculates the routing information based on the destination
networks in the topology table. The topology table includes the following information:
•
IPv4 or IPv6 address/mask—The network address and network mask for this destination.
•
Successors—The IP address and local interface connection for all feasible successors or neighbors
that advertise a shorter distance to the destination than the current feasible distance.
•
Feasibility distance (FD)—The lowest calculated distance to the destination. The feasibility distance
is the sum of the advertised distance from a neighbor plus the cost of the link to that neighbor.
DUAL uses the distance metric to select efficient, loop-free paths. DUAL selects routes to insert into the
unicast Routing Information Base (RIB) based on feasible successors. When a topology change occurs,
DUAL looks for feasible successors in the topology table. If there are feasible successors, DUAL selects
the feasible successor with the lowest feasible distance and inserts that into the unicast RIB, avoiding
unnecessary recomputation.
When there are no feasible successors but there are neighbors advertising the destination, DUAL
transitions from the passive state to the active state and triggers a recomputation to determine a new
successor or next-hop router to the destination. The amount of time required to recompute the route
affects the convergence time. EIGRP sends Query messages to all neighbors, searching for feasible
successors. Neighbors that have a feasible successor send a Reply message with that information.
Neighbors that do not have feasible successors trigger a DUAL recomputation.
EIGRP Route Updates
When a topology change occurs, EIGRP sends an Update message with only the changed routing
information to affected neighbors. This Update message includes the distance information to the new or
updated network destination.
The distance information in EIGRP is represented as a composite of available route metrics, including
bandwidth, delay, load utilization, and link reliability. Each metric has an associated weight that
determines if the metric is included in the distance calculation. You can configure these metric weights.
You can fine-tune link characteristics to achieve optimal paths, but we recommend that you use the
default settings for most configurable metrics.
This section includes the following topics:
•
Internal Route Metrics, page 8-3
•
External Route Metrics, page 8-4
•
EIGRP and the Unicast RIB, page 8-4
Internal Route Metrics
Internal routes are routes that occur between neighbors within the same EIGRP autonomous system.
These routes have the following metrics:
•
Next hop—The IP address of the next-hop router.
•
Delay—The sum of the delays configured on the interfaces that make up the route to the destination
network. Configured in tens of microseconds.
•
Bandwidth—The calculation from the lowest configured bandwidth on an interface that is part of
the route to the destination.
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Information About EIGRP
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We recommend that you use the default bandwidth value. This bandwidth parameter is also used
by EIGRP.
Note
•
MTU—The smallest maximum transmission unit value along the route to the destination.
•
Hop count—The number of hops or routers that the route passes through to the destination. This
metric is not directly used in the DUAL computation.
•
Reliability—An indication of the reliability of the links to the destination.
•
Load—An indication of how much traffic is on the links to the destination.
By default, EIGRP uses the bandwidth and delay metrics to calculate the distance to the destination. You
can modify the metric weights to include the other metrics in the calculation.
External Route Metrics
External routes are routes that occur between neighbors in different EIGRP autonomous systems. These
routes have the following metrics:
•
Next hop—The IP address of the next-hop router.
•
Router ID—The router ID of the router that redistributed this route into EIGRP.
•
AS Number—The autonomous system number of the destination.
•
Protocol ID—A code that represents the routing protocol that learned the destination route.
•
Tag—An arbitrary tag that can be used for route maps.
•
Metric—The route metric for this route from the external routing protocol.
EIGRP and the Unicast RIB
EIGRP adds all learned routes to the EIGRP topology table and the unicast RIB. When a topology
change occurs, EIGRP uses these routes to search for a feasible successor. EIGRP also listens for
notifications from the unicast RIB for changes in any routes redistributed to EIGRP from another routing
protocol.
Advanced EIGRP
You can use the advanced features of EIGRP to optimize your EIGRP configuration.
This section includes the following topics:
•
Address Families, page 8-5
•
Authentication, page 8-5
•
Stub Routers, page 8-6
•
Route Summarization, page 8-6
•
Route Redistribution, page 8-6
•
Load Balancing, page 8-6
•
Split Horizon, page 8-7
•
Virtualization Support, page 8-7
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•
Graceful Restart and High Availability, page 8-7
Address Families
EIGRP supports both IPv4 and IPv6 address families. For backward compatibility, you can configure
EIGRPv4 in route configuration mode or in IPV4 address family mode. You must configure EIGRP for
IPv6 in address family mode.
Address family configuration mode includes the following EIGRP features:
•
Authentication
•
AS number
•
Default route
•
Metrics
•
Distance
•
Graceful restart
•
Logging
•
Load balancing
•
Redistribution
•
Router ID
•
Stub router
•
Timers
You cannot configure the same feature in more than one configuration mode. For example, if you
configure the default metric in router configuration mode, you cannot configure the default metric in
address family mode.
Authentication
You can configure authentication on EIGRP messages to prevent unauthorized or invalid routing updates
in your network. EIGRP authentication supports MD5 authentication digest.
You can configure the EIGRP authentication per virtual routing and forwarding (VRF) instance or
interface using key-chain management for the authentication keys. Key-chain management allows you
to control changes to the authentication keys used by MD5 authentication digest. See the Cisco Nexus
7000 Series NX-OS Security Configuration Guide, Release 4.x, for more details about creating
key-chains.
For MD5 authentication, you configure a password that is shared at the local router and all remote
EIGRP neighbors. When an EIGRP message is created, Cisco NX-OS creates an MD5 one-way message
digest based on the message itself and the encrypted password and sends this digest along with the
EIGRP message. The receiving EIGRP neighbor validates the digest using the same encrypted password.
If the message has not changed, the calculation is identical and the EIGRP message is considered valid.
MD5 authentication also includes a sequence number with each EIGRP message that is used to ensure
that no message is replayed in the network.
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Stub Routers
You can use the EIGRP stub routing feature to improve network stability, reduce resource usage, and
simplify stub router configuration. Stub routers connect to the EIGRP network through a remote router.
See the “Stub Routing” section on page 1-7.
When using EIGRP stub routing, you need to configure the distribution and remote routers to use EIGRP
and configure only the remote router as a stub. EIGRP stub routing does not automatically enable
summarization on the distribution router. In most cases, you need to configure summarization on the
distribution routers.
Without EIGRP stub routing, even after the routes that are sent from the distribution router to the remote
router have been filtered or summarized, a problem might occur. For example, if a route is lost
somewhere in the corporate network, EIGRP could send a query to the distribution router. The
distribution router could then send a query to the remote router even if routes are summarized. If a
problem communicating over the WAN link between the distribution router and the remote router occurs,
EIGRP could get stuck in active condition and cause instability elsewhere in the network. EIGRP stub
routing allows you to prevent queries to the remote router.
Route Summarization
You can configure a summary aggregate address for a specified interface. Route summarization
simplifies route tables by replacing a number of more-specific addresses with an address that represents
all the specific addresses. For example, you can replace 10.1.1.0/24, 10.1.2.0/24, and 10.1.3.0/24 with
one summary address, 10.1.0.0/16.
If more specific routes are in the routing table, EIGRP advertises the summary address from the interface
with a metric equal to the minimum metric of the more specific routes.
Note
EIGRP does not support automatic route summarization.
Route Redistribution
You can use EIGRP to redistribute direct routes, static routes, routes learned by other EIGRP
autonomous systems, or routes from other protocols. You must configure a route map with the
redistribution to control which routes are passed into EIGRP. A route map allows you to filter routes
based on attributes such as the destination, origination protocol, route type, route tag, and so on. See
Chapter 16, “Configuring Route Policy Manager.”
You also configure the default metric that is used for all imported routes into EIGRP.
You use distribute lists to filter routes from routing updates. These filtered routes are applied to each
interface with the ip distribute-list eigrp command.
Load Balancing
You can use load balancing to allow a router to distribute traffic over all the router network ports that are
the same distance from the destination address. Load balancing increases the utilization of network
segments which increases effective network bandwidth.
Cisco NX-OS supports the Equal Cost Multiple Paths (ECMP) feature with up to 16 equal-cost paths in
the EIGRP route table and the unicast RIB. You can configure EIGRP to load balance traffic across some
or all of those paths.
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Note
EIGRP in Cisco NX-OS does not support unequal cost load balancing.
Split Horizon
You can use split horizon to ensure that EIGRP never advertises a route out of the interface where it was
learned.
Split horizon is a method that controls the sending of EIGRP update and query packets. When you enable
split horizon on an interface, Cisco NX-OS does not send update and query packets for destinations that
were learned from this interface. Controlling update and query packets in this manner reduces the
possibility of routing loops.
Split horizon with poison reverse configures EIGRP to advertise a learned route as unreachable back
through that the interface that EIGRP learned the route from.
EIGRP uses split horizon or split horizon with poison reverse in the following scenarios:
•
Exchanging topology tables for the first time between two routers in startup mode.
•
Advertising a topology table change.
•
Sending a Query message.
By default, the split horizon feature is enabled on all interfaces.
Virtualization Support
Cisco NX-OS supports multiple instances of the EIGRP protocol that runs on the same system. EIGRP
supports Virtual Routing and Forwarding instances (VRFs). VRFs exist within virtual device contexts
(VDCs). By default, Cisco NX-OS places you in the default VDC and default VRF unless you
specifically configure another VDC and VRF. See the Cisco Nexus 7000 Series NX-OS Virtual Device
Context Configuration Guide, Release 4.x and Chapter 14, “Configuring Layer 3 Virtualization.”
By default, every instance uses the same system router ID. You can optionally configure a unique router
ID for each instance.
Graceful Restart and High Availability
Cisco NX-OS supports nonstop forwarding and graceful restart for EIGRP.
You can use nonstop forwarding for EIGRP to forward data packets along known routes in the FIB while
the EIGRP routing protocol information is being restored following a failover. With NSF, peer
networking devices do not experience routing flaps. During failover, data traffic is forwarded through
intelligent modules while the standby supervisor becomes active.
If a Cisco NX-OS system experiences a cold reboot, network does not forward traffic to the system and
removes the system from the network topology. In this scenario, EIGRP experiences a stateless restart,
and all neighbors are removed. Cisco NX-OS applies the startup configuration, and EIGRP rediscovers
the neighbors and shares the full EIGRP routing information again.
A dual supervisor platform that runs Cisco NX-OS can experience a stateful supervisor switchover.
Before the switchover occurs, EIGRP uses a graceful restart to announce that EIGRP will be unavailable
for some time. During a switchover, EIGRP uses nonstop forwarding to continue forwarding traffic
based on the information in the FIB, and the system is not taken out of the network topology.
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Licensing Requirements for EIGRP
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The graceful restart-capable router uses Hello messages to notify its neighbors that an graceful restart
operation has started. When an graceful restart-aware router receives a notification from a graceful
restart-capable neighbor that a graceful restart operation is in progress, both routers immediately
exchange their topology tables. The graceful restart-aware router then performs the following actions to
assist the restarting router:
•
The router expires the EIGRP Hello hold timer to reduce the time interval set for Hello messages.
This allows the graceful restart-aware router to reply to the restarting router more quickly and
reduces the amount of time required for the restarting router to rediscover neighbors and rebuild the
topology table.
•
The router starts the route-hold timer. This timer sets the period of time that the graceful
restart-aware router will hold known routes for the restarting neighbor. The default time period is
240 seconds.
•
The router notes in the peer list that the neighbor is restarting, maintains adjacency, and holds known
routes for the restarting neighbor until the neighbor signals that it is ready for the graceful
restart-aware router to send its topology table or the route-hold timer expires. If the route-hold timer
expires on the graceful restart-aware router, the graceful restart-aware router discards held routes
and treats the restarting router as a new router joining the network and reestablishing adjacency.
After the switchover, Cisco NX-OS applies the running configuration, and EIGRP informs the neighbors
that it is operational again.
Note
You must enable graceful restart to support in-service software upgrades (ISSU) for EIGRP. If you
disable graceful restart, Cisco NX-OS issues a warning that ISSU cannot be supported with this
configuration.
Licensing Requirements for EIGRP
The following table shows the licensing requirements for this feature:
Product
License Requirement
NX-OS
EIGRP requires an Enterprise Services license. For a complete explanation of the NX-OS licensing scheme
and how to obtain and apply licenses, see the Cisco NX-OS Licensing Guide.
Prerequisites for EIGRP
EIGRP has the following prerequisites:
•
You must enable the EIGRP feature (see the “Enabling the EIGRP Feature” section on page 8-9).
•
If you configure VDCs, install the Advanced Services license and enter the desired VDC (see the
Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide, Release 4.x).
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Configuration Guidelines and Limitations
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Configuration Guidelines and Limitations
EIGRP has the following configuration guidelines and limitations:
Note
•
A metric configuration (either through the default-metric configuration option or through a route
map) is required for redistribution from any other protocol, connected routes, or static routes (see
Chapter 16, “Configuring Route Policy Manager”).
•
For graceful restart, an NSF-aware router must be up and completely converged with the network
before it can assist an NSF-capable router in a graceful restart operation.
•
For graceful restart, neighboring devices participating in the graceful restart must be NSF-aware or
NSF-capable.
•
Cisco NX-OS EIGRP is compatible with EIGRP in the Cisco IOS software.
•
Do not change the metric weights without a good reason. If you change the metric weights, you must
apply the change to all EIGRP routers in the same autonomous system.
•
Consider using stubs for larger networks.
•
Avoid redistribution between different EIGRP autonomous systems because the EIGRP vector
metric will not be preserved.
•
The no {ip | ipv6} next-hop-self command does not guarantee reachability of the next hop.
•
The {ip | ipv6} passive-interface eigrp command suppresses neighbors from forming.
•
Cisco NX-OS does not support IGRP or connecting IGRP and EIGRP clouds.
•
Autosummarization is not enabled by default.
•
Cisco NX-OS supports only IP.
If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature
might differ from the Cisco IOS commands that you would use.
Configuring Basic EIGRP
This section includes the following topics:
•
Enabling the EIGRP Feature, page 8-9
•
Creating an EIGRP Instance, page 8-10
•
Restarting an EIGRP Instance, page 8-12
•
Shutting Down an EIGRP Instance, page 8-13
•
Shutting Down EIGRP on an Interface, page 8-14
Enabling the EIGRP Feature
You must enable the EIGRP feature before you can configure EIGRP.
BEFORE YOU BEGIN
Ensure that you are in the correct VDC (or use the switchto vdc command).
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SUMMARY STEPS
1.
config t
2.
feature eigrp
3.
show feature
4.
copy running-config startup-config
DETAILED STEPS
Step 1
Command
Purpose
config t
Enters configuration mode.
Example:
switch# config t
switch(config)#
Step 2
feature eigrp
Enables the EIGRP feature.
Example:
switch(config)# feature eigrp
Step 3
show feature
Example:
switch(config)# show feature
Step 4
copy running-config startup-config
(Optional) Displays information about enabled
features.
(Optional) Saves this configuration change.
Example:
switch(config)# copy running-config
startup-config
Use the no feature eigrp command to disable the EIGRP feature and remove all associated
configuration.
Command
Purpose
no feature eigrp
Disables the EIGRP feature and removes all
associated configuration.
Example:
switch(config)# no feature eigrp
Creating an EIGRP Instance
You can create an EIGRP instance and associate an interface with that instance. You assign a unique
autonomous system number for this EIGRP process (see the “Autonomous Systems” section on
page 1-5). Routes are not advertised or accepted from other autonomous systems unless you enable route
redistribution.
BEFORE YOU BEGIN
Ensure that you have enabled the EIGRP feature (see the “Enabling the EIGRP Feature” section on
page 8-9).
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Configuring Basic EIGRP
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EIGRP must be able to obtain a router ID (for example, a configured loopback address) or you must
configure the router ID option.
If you configure an instance tag that does not qualify as an AS number, you must configure the AS
number explicitly or this EIGRP instance will remain in the shutdown state.
Ensure that you are in the correct VDC (or use the switchto vdc command).
SUMMARY STEPS
1.
config t
2.
router eigrp instance-tag
3.
autonomous-system as-number
4.
interface interface-type slot/port
5.
{ip | ipv6} router eigrp instance-tag
6.
show {ip | ipv6} eigrp interfaces
7.
copy running-config startup-config
DETAILED STEPS
Step 1
Command
Purpose
config t
Enters configuration mode.
Example:
switch# config t
switch(config)#
Step 2
router eigrp instance-tag
Example:
switch(config)# router eigrp Test1
switch(config-router)#
Step 3
autonomous-system as-number
Example:
switch(config-router)# autonomous-system
33
Step 4
log-neighbor-warnings [seconds]
Example:
switch(config-router)#
log-neighbor-warnings
If you configure an instance-tag that does not qualify
as an AS number, you must use the
autonomous-system command to configure the AS
number explicitly or this EIGRP instance will remain
in the shutdown state.
(Optional) Configures a unique AS number for this
EIGRP instance. The range is from 1 to 65535.
(Optional). Generates a system message whenever an
adjacency changes state. This command is enabled by
default.
log-adjacency-changes
Example:
switch(config-router)#
log-adjacency-changes
Step 5
Creates a new EIGRP process with the configured
instance tag. The instance tag can be any case-sensitive
alphanumeric string up to 20 characters.
(Optional) Generates a system message whenever a
neighbor warning occurs. You can configure the time
between warning messages, from 1 to 65535, in
seconds. The default is 10 seconds. This command is
enabled by default.
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Step 6
Command
Purpose
interface interface-type slot/port
Enters interface configuration mode. Use ? to
determine the slot and port ranges.
Example:
switch(config-router)# interface
ethernet 1/2
switch(config-if)#
Step 7
Associates this interface with the configured EIGRP
process. The instance tag can be any case-sensitive
Example:
alphanumeric string up to 20 characters.
switch(config-if)# ip router eigrp Test1
Step 8
show {ip | ipv6} eigrp interfaces
{ip | ipv6} router eigrp instance-tag
Displays information about EIGRP interfaces.
Example:
switch(config-if)# show ip eigrp
interfaces
Step 9
copy running-config startup-config
(Optional) Saves this configuration change.
Example:
switch(config)# copy running-config
startup-config
Use the no router eigrp command to remove the EIGRP process and the associated configuration.
Command
Purpose
no router eigrp instance-tag
Deletes the EIGRP process and all associated
configuration.
Example:
switch(config)# no router eigrp Test1
Note
You should also remove any EIGRP commands configured in interface mode if you remove the EIGRP
process.
The following example shows how to create an EIGRP process and configure an interface for EIGRP:
switch# config t
switch(config)# router eigrp Test1
switch(config)# interface ethernet 1/2
switch(config-if)# ip router eigrp Test1
switch(config-if)# no shutdown
switch(config-if)# copy running-config startup-config
For more information about other EIGRP parameters, see the “Configuring Advanced EIGRP” section
on page 8-14.
Restarting an EIGRP Instance
You can restart an EIGRP instance. This clears all neighbors for the instance.
To restart an EIGRP instance and remove all associated neighbors, use the following commands:
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Configuring Basic EIGRP
S e n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Command
Purpose
flush-routes
(Optional) Flushes all EIGRP routes in the unicast
RIB when this EIGRP instance restarts.
Example:
switch(config)# flush-routes
restart eigrp instance-tag
Example:
switch(config)# restart eigrp Test1
Restarts the EIGRP instance and removes all
neighbors. The instance tag can be any
case-sensitive alphanumeric string up to 20
characters.
Shutting Down an EIGRP Instance
You can gracefully shut down an EIGRP instance. This action emoves all routes and adjacencies but
preserves the EIGRP configuration.
To disable an EIGRP instance, use the following command in router configuration mode:
Command
Purpose
switch(config-router)# shutdown
Disables this instance of EIGRP. The EIGRP router
configuration remains.
Example:
switch(config-router)# shutdown
Configuring a Passive Interface for EIGRP
You can configure a passive interface for EIGRP. A passive interface does not participate in EIGRP
adjacency but the network address for the interfacee remains in the EIGRP topology table.
To configure a passive interface for EIGRP, use the following command in interface configuration mode:
Command
Purpose
{ip | ipv6} passive-interface eigrp
instance-tag
Suppresses EIGRP hellos, which prevents neighbors
from forming and sending routing updates on an
EIGRP interface. The instance tag can be any
case-sensitive alphanumeric string up to 20
characters.
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Configuring EIGRP
Configuring Advanced EIGRP
Se n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Shutting Down EIGRP on an Interface
You can gracefully shut down EIGRP on an interface. This action removes all adjacencies and stops
EIGRP traffic on this interface but preserves the EIGRP configuration.
To disable EIGRP on an interface, use the following command in interface configuration mode:
Command
Purpose
switch(config-if)# {ip | ipv6} eigrp
instance-tag shutdown
Disables EIGRP on this interface. The EIGRP
interface configuration remains. The instance tag can
be any case-sensitive alphanumeric string up to 20
characters.
Example:
switch(config-router)# ip eigrp Test1
shutdown
Configuring Advanced EIGRP
This section includes the following topics:
•
Configuring Authentication in EIGRP, page 8-14
•
Configuring EIGRP Stub Routing, page 8-17
•
Configuring a Summary Address for EIGRP, page 8-17
•
Redistributing Routes into EIGRP, page 8-18
•
Limiting the Number of Redistributed Routes, page 8-20
•
Configuring Load Balancing in EIGRP, page 8-22
•
Configuring Graceful Restart for EIGRP, page 8-23
•
Adjusting the Interval Between Hello Packets and the Hold Time, page 8-25
•
Disabling Split Horizon, page 8-25
•
Tuning EIGRP, page 8-26
Configuring Authentication in EIGRP
You can configure authentication between neighbors for EIGRP. See the “Authentication” section on
page 8-5.
You can configure EIGRP authentication for the EIGRP process or for individual interfaces. Interface
EIGRP authentication configuration overrides the EIGRP process-level authentication configuration.
BEFORE YOU BEGIN
Ensure that you have enabled the EIGRP feature (see the “Enabling the EIGRP Feature” section on
page 8-9).
Ensure that all neighbors for an EIGRP process share the same authentication configuration, including
the shared authentication key.
Create the key-chain for this authentication configuration. See the Cisco NX-OS Security Configuration
Guide.
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Configuring EIGRP
Configuring Advanced EIGRP
S e n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Ensure that you are in the correct VDC (or use the switchto vdc command).
SUMMARY STEPS
1.
config t
2.
router eigrp instance-tag
3.
address-family {ipv4 | ipv6} unicast
4.
authentication key-chain key-chain
5.
authentication mode md5
6.
interface interface-type slot/port
7.
{ip | ipv6} router eigrp instance-tag
8.
{ip | ipv6} authentication key-chain eigrp instance-tag key-chain
9.
{ip | ipv6} authentication mode eigrp instance-tag md5
10. copy running-config startup-config
DETAILED STEPS
Step 1
Command
Purpose
config t
Enters configuration mode.
Example:
switch# config t
switch(config)#
Step 2
router eigrp instance-tag
Example:
switch(config)# router eigrp Test1
switch(config-router)#
Step 3
address-family {ipv4 | ipv6} unicast
Example:
switch(config-router)# address-family
ipv4 unicast
switch(config-router-af)#
Step 4
authentication key-chain key-chain
Example:
switch(config-router-af)# authentication
key-chain routeKeys
Step 5
authentication mode md5
Example:
switch(config-router-af)# authentication
mode md5
Creates a new EIGRP process with the configured
instance tag. The instance tag can be any case-sensitive
alphanumeric string up to 20 characters.
If you configure an instance-tag that does not qualify
as an AS number, you must use the
autonomous-system command to configure the AS
number explicitly or this EIGRP instance will remain
in the shutdown state.
Enters the address-family configuration mode. This
command is optional for IPv4.
Associates a key chain with this EIGRP process for
this VRF. The key chain can be any case-sensitive
alphanumeric string up to 20 characters.
Configures MD5 message digest authentication mode
for this VRF.
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Step 6
Command
Purpose
interface interface-type slot/port
Enters interface configuration mode. Use ? to find the
supported interfaces.
Example:
switch(config-router-af) interface
ethernet 1/2
switch(config-if)#
Step 7
Associates this interface with the configured EIGRP
process. The instance tag can be any case-sensitive
Example:
alphanumeric string up to 20 characters.
switch(config-if)# ip router eigrp Test1
Step 8
{ip | ipv6} authentication key-chain
eigrp instance-tag key-chain
{ip | ipv6} router eigrp instance-tag
Example:
switch(config-if)# ip authentication
key-chain eigrp Test1 routeKeys
Step 9
{ip | ipv6} authentication mode eigrp
instance-tag md5
Example:
switch(config-if)# ip authentication
mode eigrp Test1 md5
Step 10
copy running-config startup-config
Associates a key chain with this EIGRP process for
this interface. This configuration overrides the
authentication configuration set in the router VRF
mode.
The instance tag can be any case-sensitive
alphanumeric string up to 20 characters.
Configures the MD5 message digest authentication
mode for this interface. This configuration overrides
the authentication configuration set in the router VRF
mode.
The instance tag can be any case-sensitive
alphanumeric string up to 20 characters.
(Optional) Saves this configuration change.
Example:
switch(config)# copy running-config
startup-config
The following example shows how to configure MD5 message digest authentication for EIGRP over
Ethernet interface 1/2:
switch# config t
switch(config)# router eigrp Test1
switch(config-router)# exit
switch(config)# interface ethernet 1/2
switch(config-if)# ip router eigrp Test1
switch(config-if)# ip authentication key-chain eigrp Test1 routeKeys
switch(config-if)# ip authentication mode eigrp Test1 md5
switch(config-if)# copy running-config startup-config
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Configuring Advanced EIGRP
S e n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Configuring EIGRP Stub Routing
To configure a router for EIGRP stub routing, use the following command in address-family
configuration mode:
Command
Purpose
switch(config-router-af)# stub [direct |
receive-only | redistributed [direct]
leak-map map-name]
Configures a remote router as an EIGRP stub router.
The map name can be any case-sensitive
alphanumeric string up to 20 characters.
Example:
switch(config-router-af)# eigrp stub
redistributed
The following example shows how to configure a stub router to advertise directly connected and
redistributed routes:
switch# config t
switch(config)# router eigrp Test1
switch(config-router)# address-family ipv6 unicast
switch(config-router-af)# stub direct redistributed
switch(config-router-af)# copy running-config startup-config
Use the show ip eigrp neighbor detail command to verify that a router has been configured as a stub
router. The last line of the output shows the stub status of the remote or spoke router. The following
example shows that output from the show ip eigrp neighbor detail command:
Router# show ip eigrp neighbor detail
IP-EIGRP neighbors for process 201
H
Address
Interface
0
Hold Uptime
SRTT
(sec)
(ms)
10.1.1.2
Se3/1
11 00:00:59
1
Version 12.1/1.2, Retrans: 2, Retries: 0
Stub Peer Advertising ( CONNECTED SUMMARY ) Routes
RTO
Q Seq Type
Cnt Num
4500 0 7
Configuring a Summary Address for EIGRP
You can configure a summary aggregate address for a specified interface. If any more specific routes are
in the routing table, EIGRP will advertise the summary address out the interface with a metric equal to
the minimum of all more specific routes. See the “Route Summarization” section on page 8-6.
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Se n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
To configure a summary aggregate address, use the following command in interface configuration mode:
Command
Purpose
switch(config-if)# {ip | ipv6}
summary-address eigrp instance-tag
ip-prefix/length [distance | leak-map
map-name]
Configures a summary aggregate address as either
an IP address and network mask, or an IP
prefix/length. The instance tag and map name can
be any case-sensitive alphanumeric string up to 20
characters.
Example:
switch(config-if)# ip summary-address
eigrp Test1 192.0.2.0/8
You can optionally configure the administrative
distance for this aggregate address. The default
administrative distance is 5 for aggregate
addresses.
The following example causes EIGRP to summarize network 192.0.2.0 out Ethernet 1/2 only:
switch(config)# interface ethernet 1/2
switch(config-if)# ip summary-address eigrp Test1 192.0.2.0 255.255.255.0
Redistributing Routes into EIGRP
You can redistribute routes in EIGRP from other routing protocols.
BEFORE YOU BEGIN
Ensure that you have enabled the EIGRP feature (see the “Enabling the EIGRP Feature” section on
page 8-9).
You must configure the metric (either through the default-metric configuration option or through a route
map) for routes redistributed from any other protocol.
You must create a route map to control the types of routes that are redistributed into EIGRP. See
Chapter 16, “Configuring Route Policy Manager.”
Ensure that you are in the correct VDC (or use the switchto vdc command).
SUMMARY STEPS
1.
config t
2.
router eigrp instance-tag
3.
address-family {ipv4 | ipv6} unicast
4.
redistribute {bgp as | {eigrp | isis | ospf | ospfv3 | rip} instance-tag | direct | static} route-map
name
5.
default-metric bandwidth delay reliability loading mtu
6.
show {ip | ipv6} eigrp route-map statistics redistribute
7.
copy running-config startup-config
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
DETAILED STEPS
Step 1
Command
Purpose
config t
Enters configuration mode.
Example:
switch# config t
switch(config)#
Step 2
router eigrp instance-tag
Example:
switch(config)# router eigrp Test1
switch(config-router)#
Creates a new EIGRP process with the
configured instance tag. The instance tag can
be any case-sensitive alphanumeric string up
to 20 characters.
If you configure an instance-tag that does not
qualify as an AS number, you must use the
autonomous-system command to configure
the AS number explicitly or this EIGRP
instance will remain in the shutdown state.
Step 3
address-family {ipv4 | ipv6} unicast
Example:
switch(config-router)# address-family ipv4
unicast
switch(config-router-af)#
Step 4
redistribute {bgp as| {eigrp | isis | ospf |
ospfv3 | rip} instance-tag | direct | static}
route-map name
Example:
switch(config-router-af)# redistribute bgp 100
route-map BGPFilter
Step 5
default-metric bandwidth delay reliability
loading mtu
Example:
switch(config-router-af)# default-metric
500000 30 200 1 1500
Step 6
show {ip | ipv6} eigrp route-map statistics
redistribute
Enters the address-family configuration mode.
This command is optional for IPv4.
Injects routes from one routing domain into
EIGRP. The instance tag and map name can be
any case-sensitive alphanumeric string up to
20 characters.
Sets the metrics assigned to routes learned
through route redistribution. The default
values are as follows:
•
bandwidth—100000 Kb/s
•
delay—100 (10 microsecond units)
•
reliability—255
•
loading—1
•
MTU—1492
Displays information about EIGRP route map
statistics.
Example:
switch(config-router-af)# show ip eigrp
route-map statistics redistribute bgp
Step 7
copy running-config startup-config
(Optional) Saves this configuration change.
Example:
switch(config)# copy running-config
startup-config
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The following example shows how to redistribute BGP into EIGRP for IPv4:
switch# config t
switch(config)# router
switch(config-router)#
switch(config-router)#
switch(config-router)#
eigrp Test1
redistribute bgp 100 route-map BGPFilter
default-metric 500000 30 200 1 1500
copy running-config startup-config
Limiting the Number of Redistributed Routes
Route redistribution can add many routes to the EIGRP route table. You can configure a maximum limit
to the number of routes accepted from external protocols. EIGRP provides the following options to
configure redistributed route limits:
•
Fixed limit—Logs a message when EIGRP reaches the configured maximum. EIGRP does not
accept any more redistributed routes. You can optionally configure a threshold percentage of the
maximum where EIGRP will log a warning when that threshold is passed.
•
Warning only—Logs a warning only when EIGRP reaches the maximum. EIGRP continues to
accept redistributed routes.
•
Withdraw—Start the timeout period when EIGRP reaches the maximum. After the timeout period,
EIGRP requests all redistributed routes if the current number of redistributed routes is less than the
maximum limit. If the current number of redistributed routes is at the maximum limit, EIGRP
withdraws all redistributed routes. You must clear this condition before EIGRP accepts more
redistributed routes.
You can optionally configure the timeout period.
BEFORE YOU BEGIN
Ensure that you have enabled the EIGRP feature (see the “Enabling the EIGRP Feature” section on
page 8-9).
Ensure that you are in the correct VDC (or use the switchto vdc command).
SUMMARY STEPS
1.
config t
2.
router eigrp instance-tag
3.
redistribute {bgp id | direct | eigrp id | isis id | ospf id | rip id | static} route-map map-name
4.
redistribute maximum-prefix max [threshold] [warning-only | withdraw [num-retries timeout]]
5.
show running-config eigrp
6.
copy running-config startup-config
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DETAILED STEPS
Step 1
Command
Purpose
config t
Enters configuration mode.
Example:
switch# config t
switch(config)#
Step 2
router eigrp instance-tag
Example:
switch(config)# router eigrp Test1
switch(config-router)#
Step 3
redistribute {bgp id | direct | eigrp id
| isis id | ospf id | rip id | static}
route-map map-name
Creates a new EIGRP instance with the configured
instance tag.
Redistributes the selected protocol into EIGRP
through the configured route map.
Example:
switch(config-router)# redistribute bgp
route-map FilterExternalBGP
Step 4
redistribute maximum-prefix max
[threshold] [warning-only | withdraw
[num-retries timeout]]
Example:
switch(config-router)# redistribute
maximum-prefix 1000 75 warning-only
Step 5
show running-config eigrp
Specifies a maximum number of prefixes that EIGRP
will distribute. The range is from 0 to 65536.
Optionally specifies the following:
•
threshold—Percent of maximum prefixes that will
trigger a warning message.
•
warning-only—Logs an warning message when
the maximum number of prefixes is exceeded.
•
withdraw—Withdraws all redistributed routes.
Optionally tries to retrieve the redistributed
routes. The num-retries range is from 1 to 12. The
timeout is from 60 to 600 seconds. The default is
300 seconds. Use clear ip eigrp redistribution if
all routes are withdrawn.
(Optional) Displays the EIGRP configuration.
Example:
switch(config-router)# show
running-config eigrp
Step 6
copy running-config startup-config
(Optional) Saves this configuration change.
Example:
switch(config-router)# copy
running-config startup-config
The following example shows how to limit the number of redistributed routes into EIGRP:
switch# config t
switch(config)# router eigrp Test1
switch(config-router)# redistribute bgp route-map FilterExternalBGP
switch(config-router)# redistribute maximum-prefix 1000 75
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Configuring Advanced EIGRP
Se n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Configuring Load Balancing in EIGRP
You can configure load balancing in EIGRP. You can configure the number of Equal Cost Multiple Path
(ECMP) routes using the maximum paths option. See the “Configuring Load Balancing in EIGRP”
section on page 8-22.
BEFORE YOU BEGIN
Ensure that you have enabled the EIGRP feature (see the “Enabling the EIGRP Feature” section on
page 8-9).
Ensure that you are in the correct VDC (or use the switchto vdc command).
SUMMARY STEPS
1.
config t
2.
router eigrp instance-tag
3.
address-family {ipv4 | ipv6} unicast
4.
maximum-paths num-paths
5.
copy running-config startup-config
DETAILED STEPS
Step 1
Command
Purpose
config t
Enters configuration mode.
Example:
switch# config t
switch(config)#
Step 2
router eigrp instance-tag
Example:
switch(config)# router eigrp Test1
switch(config-router)#
Creates a new EIGRP process with the
configured instance tag. The instance tag can
be any case-sensitive alphanumeric string up
to 20 characters.
If you configure an instance-tag that does not
qualify as an AS number, you must use the
autonomous-system command to configure
the AS number explicitly or this EIGRP
instance will remain in the shutdown state.
Step 3
address-family {ipv4 | ipv6} unicast
Example:
switch(config-router)# address-family ipv4
unicast
switch(config-router-af)#
Enters the address-family configuration mode.
This command is optional for IPv4.
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Step 4
Step 5
Command
Purpose
maximum-paths num-paths
Example:
switch(config-router-af)# maximum-paths 5
Sets the number of equal cost paths that
EIGRP will accept in the route table. The
range is from 1 to 16. The default is 8.
copy running-config startup-config
(Optional) Saves this configuration change.
Example:
switch(config-router-af)# copy running-config
startup-config
The following example shows how to configure equal cost load balancing for EIGRP over IPv4 with a
maximum of six equal cost paths:
switch# config t
switch(config)# router eigrp Test1
switch(config-router)# maximum-paths 6
switch(config-router)# copy running-config startup-config
Configuring Graceful Restart for EIGRP
You can configure graceful restart or nonstop forwarding for EIGRP. See the “Graceful Restart and High
Availability” section on page 8-7.
Note
Graceful restart is enabled by default.
BEFORE YOU BEGIN
Ensure that you have enabled the EIGRP feature (see the “Enabling the EIGRP Feature” section on
page 8-9).
An NSF-aware router must be up and completely converged with the network before it can assist an
NSF-capable router in a graceful restart operation.
Neighboring devices participating in the graceful restart must be NSF-aware or NSF-capable.
Ensure that you are in the correct VDC (or use the switchto vdc command).
SUMMARY STEPS
1.
config t
2.
router eigrp instance-tag
3.
address-family {ipv4 | ipv6} unicast
4.
graceful-restart
5.
timers nsf converge seconds
6.
timers nsf route-hold seconds
7.
timers nsf signal seconds
8.
copy running-config startup-config
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Configuring Advanced EIGRP
Se n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
DETAILED STEPS
Step 1
Command
Purpose
config t
Enters configuration mode.
Example:
switch# config t
switch(config)#
Step 2
router eigrp instance-tag
Example:
switch(config)# router eigrp Test1
switch(config-router)#
Creates a new EIGRP process with the
configured instance tag. The instance tag can
be any case-sensitive alphanumeric string up
to 20 characters.
If you configure an instance-tag that does not
qualify as an AS number, you must use the
autonomous-system command to configure
the AS number explicitly or this EIGRP
instance will remain in the shutdown state.
Step 3
address-family {ipv4 | ipv6} unicast
Example:
switch(config-router)# address-family ipv4
unicast
switch(config-router-af)#
Step 4
graceful-restart
Example:
switch(config-router-af)# graceful-restart
Step 5
timers nsf converge seconds
Example:
switch(config-router-af)# timers nsf converge
100
Step 6
timers nsf route-hold seconds
Example:
switch(config-router-af)# timers nsf
route-hold 200
Step 7
Step 8
Enters the address-family configuration mode.
This command is optional for IPv4.
Enables graceful restart. This feature is
enabled by default.
Sets the time limit for the convergence after a
switchover. The range is from 60 to 180
seconds. The default is 120.
Sets the hold time for routes learned from the
graceful restart-aware peer. The range is from
20 to 300 seconds. The default is 240.
Example:
switch(config-router-af)# timers nsf signal 15
Sets the time limit for signaling a graceful
restart. The range is from 10 to 30 seconds.
The default is 20.
copy running-config startup-config
(Optional) Saves this configuration change.
timers nsf signal seconds
Example:
switch(config-router-af)# copy running-config
startup-config
The following example shows how to configure graceful restart for EIGRP over IPv6 using the default
timer values:
switch# config t
switch(config)# router eigrp Test1
switch(config-router)# address-family ipv6 unicast
switch(config-router-af)# graceful-restart
switch(config-router-af)# copy running-config startup-config
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Configuring EIGRP
Configuring Advanced EIGRP
S e n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Adjusting the Interval Between Hello Packets and the Hold Time
You can adjust the interval between Hello messages and the hold time.
By default, Hello messages are sent every 5 seconds. The hold time is advertised in Hello messages and
indicates to neighbors the length of time that they should consider the sender valid. The default hold time
is three times the hello interval, or 15 seconds.
To change the interval between hello packets, use the following command in interface configuration
mode:
Command
Purpose
switch(config-if)# {ip | ipv6}
hello-interval eigrp instance-tag
seconds
Configures the hello interval for an EIGRP routing
process. The instance tag can be any case-sensitive
alphanumeric string up to 20 characters. The range is
from 1 to 65535 seconds. The default is 5.
Example:
switch(config-if)# ip hello-interval
eigrp Test1 30
On very congested and large networks, the default hold time might not be sufficient time for all routers
to receive hello packets from their neighbors. In this case, you might want to increase the hold time.
To change the hold time, use the following command in interface configuration mode:
Command
Purpose
switch(config-if)# {ip | ipv6}
hold-time eigrp instance-tag seconds
Configures the hold time for an EIGRP routing process.
The instance tag can be any case-sensitive
alphanumeric string up to 20 characters. The range is
from 1 to 65535.
Example:
switch(config-if)# ipv6 hold-time eigrp
Test1 30
Use the show ip eigrp interface detail command to verify timer configuration.
Disabling Split Horizon
You can use split horizon to block route information from being advertised by a router out of any
interface from which that information originated. Split horizon usually optimizes communications
among multiple routing devices, particularly when links are broken.
By default, split horizon is enabled on all interfaces.
To disable split horizon, use the following command in interface configuration mode:
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Configuring EIGRP
Configuring Advanced EIGRP
Se n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Command
Purpose
switch(config-if)# no {ip | ipv6}
split-horizon eigrp instance-tag
Disables split horizon.
Example:
switch(config-if)# no ip split-horizon eigrp
Test1
Tuning EIGRP
You can configure optional parameters to tune EIGRP for your network.
You can configure the following optional parameters in address-family configuration mode:
Command
Purpose
default-information originate [always |
route-map map-name]
Originates or accepts the default route with prefix
0.0.0.0/0. When a route-map is supplied, the
default route is originated only when the route map
yields a true condition. The map name can be any
case-sensitive alphanumeric string up to 20
characters.
Example:
switch(config-router-af)#
default-information originate always
distance internal external
Example:
switch(config-router-af)# distance 25 100
metric max-hops hop-count
Example:
switch(config-router-af)# metric max-hops
70
Configures the administrative distance for this
EIGRP process. The range is from 1 to 255. The
internal value sets the distance for routes learned
from within the same autonomous system (the
default value is 90). The external value sets the
distance for routes learned from an external
autonomous system (the default value is 170).
Sets maximum allowed hops for an advertised
route. Routes over this maximum are advertised as
unreachable. The range is from 1 to 255. The
default is 100.
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Configuring Advanced EIGRP
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Command
Purpose
metric weights tos k1 k2 k3 k4 k5
Adjusts the EIGRP metric or K value. EIGRP uses
the following formula to determine the total metric
to the network:
Example:
switch(config-router-af)# metric weights 0
1 3 2 1 0
metric = [k1*bandwidth + (k2*bandwidth)/(256 –
load) + k3*delay] * [k5/(reliability + k4)]
Default values and ranges are as follows:
timers active-time {time-limit | disabled}
Example:
switch(config-router-af)# timers
active-time 200.
•
TOS—0. The range is from 0 to 8.
•
k1—1. The range is from 0 to 255.
•
k2—0. The range is from 0 to 255.
•
k3—1. The range is from 0 to 255.
•
k4—0. The range is from 0 to 255.
•
k5—0. The range is from 0 to 255.
Sets the time the router waits in minutes (after
sending a query) before declaring the route to be
stuck in the active (SIA) state. The range is from 1
to 65535. The default is 3.
You can configure the following optional parameters in interface configuration mode:
Command
Purpose
{ip | ipv6} bandwidth eigrp instance-tag
bandwidth
Configures the bandwidth metric for EIGRP on an
interface. The instance tag can be any
case-sensitive alphanumeric string up to 20
characters. The bandwidth range is from 1 to
2,560,000,000 Kb/s.
Example:
switch(config-if)# ip bandwidth eigrp
Test1 30000
{ip | ipv6} bandwidth-percent eigrp
instance-tag percent
Example:
switch(config-if)# ip bandwidth-percent
eigrp Test1 30
no {ip | ipv6} delay eigrp instance-tag
delay
Example:
switch(config-if)# ip delay eigrp Test1
100
{ip | ipv6} distribute-list eigrp
instance-tag
{prefix-list name| route-map name} {in |
out}
Configures the percentage of bandwidth that
EIGRP might use on an interface. The instance tag
can be any case-sensitive alphanumeric string up to
20 characters.
The percent range is from 0 to 100. The default is
50.
Configures the delay metric for EIGRP on an
interface. The instance tag can be any
case-sensitive alphanumeric string up to 20
characters. The delay range is from 1 to 16777215
(in tens of microseconds).
Configures the route filtering policy for EIGRP on
this interface. The instance tag, prefix list name,
and route map name can be any case-sensitive
alphanumeric string up to 20 characters.
Example:
switch(config-if)# ip distribute-list
eigrp Test1 route-map EigrpTest in
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Configuring EIGRP
Configuring Virtualization for EIGRP
Se n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Command
Purpose
no {ip | ipv6} next-hop-self eigrp
instance-tag
Configures EIGRP to use the received next-hop
address rather than the address for this interface.
The default is to use the IP address of this interface
for the next-hop address. The instance tag can be
any case-sensitive alphanumeric string up to 20
characters.
Example:
switch(config-if)# ipv6 next-hop-self
eigrp Test1
{ip | ipv6} offset-list eigrp instance-tag
{prefix-list name| route-map name} {in |
out} offset
Example:
switch(config-if)# ip offfset-list eigrp
Test1 prefix-list EigrpList in
{ip | ipv6} passive-interface eigrp
instance-tag
Example:
switch(config-if)# ip passive-interface
eigrp Test1
Adds an offset to incoming and outgoing metrics to
routes learned by EIGRP. The instance tag, prefix
list name, and route map name can be any
case-sensitive alphanumeric string up to 20
characters.
Suppresses EIGRP hellos, which prevents
neighbors from forming and sending routing
updates on an EIGRP interface. The instance tag
can be any case-sensitive alphanumeric string up to
20 characters.
Configuring Virtualization for EIGRP
You can configure multiple EIGRP processes in each VDC. You can also create multiple VRFs within
each VDC and use the same or multiple EIGRP processes in each VRF. You assign an interface to a VRF
Note
Configure all other parameters for an interface after you configure the VRF for an interface. Configuring
a VRF for an interface deletes all other configuration for that interface.
BEFORE YOU BEGIN
Ensure that you have enabled the EIGRP feature (see the “Enabling the EIGRP Feature” section on
page 8-9).
Create the VDCs and VRFs.
Ensure that you are in the correct VDC (or use the switchto vdc command).
SUMMARY STEPS
1.
config t
2.
vrf context vrf-name
3.
router eigrp instance-tag
4.
interface ethernet slot/port
5.
vrf member vrf-name
6.
{ip | ipv6} router eigrp instance-tag
7.
copy running-config startup-config
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DETAILED STEPS
Step 1
Command
Purpose
config t
Enters configuration mode.
Example:
switch# config t
switch(config)#
Step 2
vrf context vrf-name
Example:
switch(config)# vrf context
RemoteOfficeVRF
switch(config-vrf)#
Step 3
router eigrp instance-tag
Example:
switch(config)# router eigrp Test1
switch(config-router)#
Step 4
interface ethernet slot/port
Example:
switch(config)# interface ethernet 1/2
switch(config-if)#
Step 5
vrf member vrf-name
Example:
switch(config-if)# vrf member
RemoteOfficeVRF
Creates a new VRF and enters VRF configuration
mode. The VRN name can be any case-sensitive
alphanumeric string up to 20 characters.
Creates a new EIGRP process with the configured
instance tag. The instance tag can be any case-sensitive
alphanumeric string up to 20 characters.
If you configure an instance-tag that does not qualify
as an AS number, you must use the
autonomous-system command to configure the AS
number explicitly or this EIGRP instance will remain
in the shutdown state.
Enters interface configuration mode. Use ? to find the
slot and port ranges.
Adds this interface to a VRF. The VRF name can be
any case-sensitive alphanumeric string up to 20
characters.
Step 6
Adds this interface to the EIGRP process. The instance
tag can be any case-sensitive alphanumeric string up to
Example:
20 characters.
switch(config-if)# ip router eigrp Test1
Step 7
copy running-config startup-config
{ip | ipv6} router eigrp instance-tag
(Optional) Saves this configuration change.
Example:
switch(config-if)# copy running-config
startup-config
The following example shows how to create a VRF and add an interface to the VRF:
switch# config t
switch(config)# vrf context NewVRF
switch(config-vrf)# router eigrp Test1
switch(config-router)# interface ethernet 1/2
switch(config-if)# ip router eigrp Test1
switch(config-if)# vrf member NewVRF
switch(config-if)# copy running-config startup-config
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Verifying EIGRP Configuration
Se n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Verifying EIGRP Configuration
To verify the EIGRP configuration, use the following commands:
Command
Purpose
show {ip | ipv6} eigrp [instance-tag]
Displays a summary of the configured EIGRP processes.
show {ip | ipv6} eigrp [instance-tag]
interfaces [type number] [brief] [detail]
Displays information about all configured EIGRP
interfaces.
show {ip | ipv6} eigrp instance-tag
neighbors [type number] [detail]
Displays information about all the EIGRP neighbors. Use
this command to verify the EIGRP neighbor
configuration.
show {ip | ipv6} eigrp [instance-tag] route Displays information about all the EIGRP routes.
[ip-prefix/length] [active] [all-links]
[detail-links] [pending] [summary]
[zero-successors] [vrf vrf-name]
show {ip | ipv6} eigrp [instance-tag]
topology [ip-prefix/length] [active]
[all-links] [detail-links] [pending]
[summary] [zero-successors] [vrf
vrf-name]
Displays information about the EIGRP topology table.
show running-configuration eigrp
Displays the current running EIGRP configuration.
Displaying EIGRP Statistics
To display EIGRP statistics, use the following commands:
Command
Purpose
show {ip | ipv6} eigrp [instance-tag]
accounting [vrf vrf-name]
Displays accounting statistics for EIGRP.
show {ip | ipv6} eigrp [instance-tag]
route-map statistics redistribute
Displays redistribution statistics for EIGRP.
show {ip | ipv6} eigrp [instance-tag]
traffic [vrf vrf-name]
Displays traffic statistics for EIGRP.
EIGRP Example Configuration
The following example shows how to configure EIGRP:
feature eigrp
interface ethernet 1/2
ip address 192.0.2.55/24
ip router eigrp Test1
no shutdown
router eigrp Test1
router-id 192.0.2.1
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Related Topics
S e n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Related Topics
See Chapter 16, “Configuring Route Policy Manager” for more information on route maps.
Default Settings
Table 8-1 lists the default settings for EIGRP parameters.
Table 8-1
Default EIGRP Parameters
Parameters
Default
Administrative distance
Bandwidth percent
•
Internal routes—90
•
External routes—170
50 percent
Default metric for redistributed routes
•
bandwidth—100000 Kb/s
•
delay—100 (10 microsecond units)
•
reliability—255
•
loading—1
•
MTU—1500
EIGRP feature
Disabled
Hello interval
5 seconds
Hold time
15 seconds
Equal-cost paths
8
Metric weights
10100
Next-hop address advertised
IP address of local interface
NSF convergence time
120
NSF route-hold time
240
NSF signal time
20
Redistribution
Disabled
Split horizon
Enabled
Additional References
For additional information related to implementing EIGRP, see the following sections:
•
Related Documents, page 8-32
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Feature History for EIGRP
Se n d d o c u m e n t c o m m e n t s t o n ex u s 7 k - d o c f e e d b a ck @ c i s c o . c o m .
Related Documents
Related Topic
Document Title
EIGRP CLI commands
Cisco Nexus 7000 Series NX-OS Unicast Routing Command
Reference
VDCs and VRFs
Cisco Nexus 7000 Series NX-OS Virtual Device Context
Configuration Guide, Release 4.x
http://www.cisco.com/warp/public/103/1.html
Introduction to EIGRP Tech Note
http://www.cisco.com/en/US/tech/tk365/technologies
_q_and_a_item09186a008012dac4.shtml
EIGRP Frequently Asked Questions
MIBs
MIBs
MIBs Link
CISCO-EIGRP-MIB
To locate and download MIBs, go to the following URL:
http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml
Feature History for EIGRP
Table 8-2 lists the release history for this feature.
Table 8-2
Feature History for EIGRP
Feature Name
Releases
Feature Information
Graceful shutdown
4.2(1)
Added support to gracefully shut down an EIGRP instance
or EIGRP on an interface but preserve the EGIRP
configuration.
EIGRP instance tag
4.2(1)
Changed length to 20 characters.
Limits on redistributed routes
4.2(1)
Added support for limiting the number of redistributed
routes.
EIGRP IPv6 support
4.1(2)
Added support for IPv6.
Authentication
4.0(3)
Added the ability to configure authentication within a VRF
for EIGRP.
EIGRP
4.0(1)
This feature was introduced.
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