ARP Commands
Note
All commands applicable for the Cisco NCS 5500 Series Router are also supported on the Cisco NCS 540
Series Router that is introduced from Cisco IOS XR Release 6.3.2. References to earlier releases in
Command History tables apply to only the Cisco NCS 5500 Series Router.
This chapter describes the commands used to configure and monitor the Address Resolution Protocol (ARP)
on NCS 5000 routers.
For detailed information about ARP concepts, configuration tasks, and examples, refer to the IP Addresses
and Services Configuration Guide for Cisco NCS 5500 Series Routers.
• arp, page 2
• arp gratuitous ignore, page 3
• arp learning, page 4
• arp purge-delay, page 5
• arp timeout, page 6
• clear arp-cache, page 7
• local-proxy-arp, page 8
• priority-timeout, page 9
• proxy-arp, page 10
• route distance, page 11
• route metric, page 12
• show arp, page 13
• show arp traffic, page 16
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
arp
arp
To add a permanent entry in the Address Resolution Protocol (ARP) cache, use the arp command in XR
Config mode. To remove an entry from the ARP cache, enter the no form of this command.
arp [vrf vrf-name] ip-address hardware-address encapsulation-type [alias]
no arp [vrf vrf-name] ip-address hardware-address encapsulation-type [alias]
Syntax Description
vrf
(Optional) Specifies VPN routing and forwarding (VRF) instance.
vrf-name
(Optional) VRF instance that identifies a VPN.
ip-address
IPv4 (network layer) address for which a permanent entry is added to the ARP
cache. Enter the IPv4 address in a four-part dotted-decimal format that corresponds
to the local data-link address (a 32-bit address).
hardware-address
Hardware (data link layer) address that the IPv4 address is linked to. Enter the
local data-link address (a 48-bit address), such as 0800.0900.1834.
encapsulation-type
Encapsulation type. The encapsulation types are:
• arpa
• srp
• srpa
• srpb
For Ethernet interfaces, this is typically the arpa keyword.
alias
(Optional) Causes the software to respond to ARP requests as if it were the owner
of both the specified IP address and hardware address, whether proxy ARP is
enabled or not.
Command Default
No entries are permanently installed in the ARP cache.
Command Modes
XR Config mode
Command History
Release
Modification
Release 6.0
This command was introduced.
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
arp gratuitous ignore
Usage Guidelines
The software uses ARP cache entries to translate 32-bit IP addresses into 48-bit hardware addresses.
Because most hosts support dynamic resolution, you generally need not specify static ARP cache entries.
Static entries are permanent entries that map a network layer address (IPv4 address) to a data-link layer address
(MAC address). If the alias keyword is specified when creating the entry, the interface to which the entry
is attached will act as if it is the owner of the specified addresses, that is, it will respond to ARP request packets
for this network layer address with the data link layer address in the entry.
The software does not respond to any ARP requests received for the specified IP address unless proxy ARP
is enabled on the interface on which the request is received. When proxy ARP is enabled, the software responds
to ARP requests with its own local interface hardware address.
To remove all nonstatic entries from the ARP cache, enter the clear arp-cache, on page 7 in XR EXEC
mode.
Task ID
Task ID
Operations
cef
read, write
The following is an example of a static ARP entry for a typical Ethernet host:
RP/0/RP0/CPU0:router# configure
RP/0/RP0/CPU0:router(config)# arp 192.168.7.19 0800.0900.1834 arpa
arp gratuitous ignore
To ignore receipt of gratuitous Address Resolution Protocol (ARP) packets, use the arp gratuitous ignore
command in interface configuration mode. To receipt gratuitous ARP packets, use the no form of this command.
arp gratuitous ignore
no arp gratuitous ignore
Syntax Description
This command has no keywords or arguments.
Command Default
Disabled
Command Modes
Interface configuration
Command History
Release
Modification
Release 6.0
This command was introduced.
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
arp learning
Usage Guidelines
Task ID
No specific guidelines impact the use of this command.
Task ID
Operations
cef
write
This example shows how to configure arp gratuitous ignore command:
RP/0/# configure
RP/0/(config)# interface HundredGigE 0/1/0/0
RP/0/(config-if)# arp gratuitous ignore
arp learning
To enable the dynamic learning of ARP entries for a local subnet or all subnets, use the arp learning command.
To disable this command, use the no prefix or the disable option for this command.
arp learning local
no arp learning local
arp learning disable
no arp learning disable
Syntax Description
local
Enables the dynamic learning of ARP entries for local subnets.
When arp learning local is configured on an interface or sub-interface, it learns only
the ARP entries from ARP packets on the same subnet.
disable
Disables the dynamic learning of all ARP entries.
Command Default
This command has no keywords or arguments.
Command Modes
Sub-interface configuration mode
Usage Guidelines
RP/0/RP0/CPU0:router(config)#interface GigabitEthernet 0/0/0/1
RP/0/RP0/CPU0:router(config-if)# ipv4 address 12.1.3.4 255.255.255.0
RP/0/RP0/CPU0:router(config-if)# arp learning local
RP/0/RP0/CPU0:router(config-if)# no shut
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
arp purge-delay
RP/0/RP0/CPU0:router(config-if)# commit
RP/0/RP0/CPU0:router(config)# interface GigabitEthernet 0/0/0/1
RP/0/RP0/CPU0:router(config-if)# ipv4 address 12.1.3.4 255.255.255.0
RP/0/RP0/CPU0:router(config-if)# arp learning disable
RP/0/RP0/CPU0:router(config-if)# commit
arp purge-delay
To delay purging Address Resolution Protocol (ARP) entries when an interface goes down, use the arp
purge-delay command in interface configuration mode. To turn off the purge delay feature, use the no form
of this command.
arp purge-delay value
no arp purge-delay value
Syntax Description
value
Sets the purge delay time in seconds. Range is 1 to 65535.
Command Default
Default value is off.
Command Modes
Interface configuration
Command History
Usage Guidelines
Task ID
Release
Modification
Release 6.0
This command was introduced.
Use the arp purge-delay command to delay purging ARP entries when an interface goes down. If the interface
comes up within the delay time, then the ARP entries are restored to prevent packet loss with Equal Cost
Multipath (ECMP) configured.
Task ID
Operations
cef
read, write
The following is an example of setting the purge delay to 50 seconds:
RP/0/# configure
RP/0/(config)# interface HundredGigE 0/0/0/0
RP/0/(config-if)# arp purge-delay 50
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
arp timeout
arp timeout
To specify the duration of dynamic entries learned on an interface remain in the Address Resolution Protocol
(ARP) cache, enter the arp timeout command in interface configuration mode. To remove the arp timeout
command from the configuration file and restore the system to its default condition with respect to this
command, enter the no form of this command.
arp timeout seconds
no arp timeout seconds
Syntax Description
seconds
Indicates the time, in seconds, for which an entry remains in the ARP cache. Range
is 30 to 4294967295.
Command Default
Entries remain in the ARP cache for 14,400 seconds (4 hours).
Command Modes
Interface configuration
Command History
Usage Guidelines
Release
Modification
Release 6.0
This command was supported.
This command is ignored when issued on interfaces that do not use ARP. Also, ARP entries that correspond
to the local interface or that are statically configured by the user never time out.
The arp timeout command applies only to the interface that is entered. When the timeout is changed for an
interface the change applies only to that interface.
The show interfaces command displays the ARP timeout value in hours:minutes:seconds, as follows:
ARP type: ARPA, ARP Timeout 04:00:00
Task ID
Task ID
Operations
cef
read, write
The following example shows how to set the ARP timeout to 3600 seconds to allow entries to time out more
quickly than the default:
RP/0/#configure
RP/0/(config)#interface HundredGigE 0/0/0/0
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
clear arp-cache
RP/0/(config-if)# arp timeout 3600
clear arp-cache
To delete all dynamic entries from the Address Resolution Protocol (ARP) cache, clear the fast-switching
cache, and clear the IP route cache, use the clear arp-cache command in .
clear arp-cache {traffic type interface-path-id| location node-id}
Syntax Description
traffic
Deletes traffic statistics on the specified interface.
t ype
Interface type. For more information, use the question mark (?) online help function.
interface- path-id
Either a physical interface instance or a virtual interface instance as follows:
• Physical interface instance. Naming notation is rack/slot/module/port and a slash
between values is required as part of the notation.
◦rack: Chassis number of the rack.
◦slot: Physical slot number of the modular services card or line card.
◦module: Module number. A physical layer interface module (PLIM) is
always 0.
◦port: Physical port number of the interface.
• Virtual interface instance. Number range varies depending on interface type.
For more information about the syntax for the router, use the question mark (?) online
help function.
location node-id
Command Default
Clears the ARP entries for a specified location. The node-id argument is entered in
the rack/slot/module notation.
No default behavior or values
Command Modes
Command History
Release
Modification
Release 6.0
This command was introduced.
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
local-proxy-arp
Usage Guidelines
Task ID
When issued without keywords or arguments, the clear arp-cache command clears all entries in the ARP
cache.
Task ID
Operations
cef
execute
The following example shows how to remove traffic statistic entries from the ARP cache that match the
specified interface:
RP/0/# clear arp-cache traffic tengige 0/1/0/0 location 0/1/CPU0
The following example shows how to remove entries from the ARP cache that match the specified location:
RP/0/# clear arp-cache location 0/1/CPU0
local-proxy-arp
To enable local proxy Address Resolution Protocol (ARP) on an interface, enter the local-proxy-arp command
in interface configuration mode. To disable local proxy ARP on the interface, enter the no form of this
command.
local-proxy-arp
no local-proxy-arp
Syntax Description
This command has no keywords or arguments.
Command Default
Local proxy ARP is disabled on all interfaces.
Command Modes
Interface configuration
Command History
Usage Guidelines
Release
Modification
Release 6.0
This command was introduced.
When local proxy ARP is enabled, the networking device responds to ARP requests that meet all the following
conditions:
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
priority-timeout
• The target IP address in the ARP request, the IP address of the ARP source, and the IP address of the
interface on which the ARP request is received are on the same Layer 3 network.
• The next hop for the target IP address is through the same interface as the request is received.
Typically, local proxy ARP is used to resolve MAC addresses to IP addresses in the same Layer 3 network
such as, private VLANs that are Layer 2-separated. Local proxy ARP supports all types of interfaces supported
by ARP and unnumbered interfaces.
Using the no form of the command removes the specified command from the configuration file and restores
the system to its default condition with respect to the command.
Task ID
Task ID
Operations
cef
read, write
priority-timeout
To configure the timer to time out a high-priority Direct Attached Gateway Redundancy (DAGR) route and
reverting to normal priority, use the priority-timeout command in DAGR peer interface configuration mode.
priority-timeout time
Syntax Description
time
Time in seconds after which a high-priority route reverts to a normal priority route. The
range of values is 1 to 10000.
Command Default
Default for time is 20 seconds.
Command Modes
DAGR peer interface configuration
Command History
Usage Guidelines
Release
Modification
Release 6.0
This command was introduced.
To use this command, you must be in a user group associated with a task group that includes the proper task
IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA
administrator for assistance.
When this function is applied, the DAGR group configuration is updated in the database.
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
proxy-arp
The new timer values take effect the next time the timer is set. No immediate timer restarts are triggered on
the basis of this event.
Task ID
Task ID
Operations
cef
write
The following example configures a priority timeout of 25 seconds:
RP/0/(config-if-dagr-peer)# priority-timeout 25
RP/0/(config-if-dagr-peer)#
proxy-arp
To enable proxy Address Resolution Protocol (ARP) on an interface, enter the proxy-arp command in interface
configuration mode. To disable proxy ARP on the interface, enter the no form of this command.
proxy-arp
no proxy-arp
Syntax Description
This command has no keywords or arguments.
Command Default
Proxy ARP is disabled on all interfaces.
Command Modes
Interface configuration
Command History
Usage Guidelines
Release
Modification
Release 6.0
This command was introduced.
When proxy ARP is disabled, the networking device responds to ARP requests received on an interface only
if one of the following conditions is met:
• The target IP address in the ARP request is the same as the interface IP address on which the request is
received.
• The target IP address in the ARP request has a statically configured ARP alias.
When proxy ARP is enabled, the networking device also responds to ARP requests that meet all of the following
conditions:
• The target IP address is not on the same physical network (LAN) on which the request is received.
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ARP Commands
route distance
• The networking device has one or more routes to the target IP address.
• All of the routes to the target IP address go through interfaces other than the one on which the request
is received.
Using the no form of the command removes the specified command from the configuration file and restores
the system to its default condition with respect to the command.
Task ID
Task ID
Operations
cef
read, write
The following example shows how to enable proxy ARP on HundredGigE interface 0/0/0/0:
RP/0/#(config)# interface HundredGigE 0/0/0/0
RP/0/#(config-if)# proxy-arp
route distance
To configure route distance for a given Direct Attached Gateway Redundancy (DAGR) group, use the route
distance command in DAGR peer interface configuration mode.
route distance normal normal-distance priority priority-distance
Syntax Description
normal normal-distance
Sets normal route (administrative) distance. Range is 0 to 256.
priority priority-distance
Sets priority route (administrative) distance. Range is 0 to 256.
Command Default
Default for normal-distance default is 150 and the default for priority-distance is 5.
Command Modes
DAGR peer interface configuration
Command History
Usage Guidelines
Release
Modification
Release 6.0
This command was introduced.
The default setting for a priority distance takes precedence over that of a typical Internet Gateway Protocol
(IGP). The normal distance setting does not.
When this setting is applied, the DAGR group is updated in the database.
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
route metric
Task ID
Task ID
Operations
cef
write
The following example configures a DAGR group peer with a normal route distance of 48 and priority route
distance of 5:
RP/0/(config-if-dagr-peer)# route distance normal 48 priority 5
RP/0/(config-if-dagr-peer)#
route metric
To configure normal and priority route metrics for a given Direct Attached Gateway Redundancy (DAGR)
group, use the route metric command in DAGR peer interface configuration mode.
route metric normal normal-metric priority priority-metric
Syntax Description
normal normal-metric
Sets a normal value for routes installed in the Routing Information
Base (RIB). The range of values is 0 to 256.
priority priority-metric
Sets a priority value for routes installed in the RIB. The range of values
is 0 to 256.
Command Default
The default for normal-metric is 100, and the default for priority-metric is 90.
Command Modes
DAGR peer interface configuration
Command History
Usage Guidelines
Release
Modification
Release 6.0
This command was introduced.
The route metric values are of less significance than the route distance command values. Setting a route
metric allows the configuration of values for routers installed in the RIB.
When this setting is applied, the DAGR group is updated in the database.
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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ARP Commands
show arp
Task ID
Task ID
Operations
cef
write
The following example configures a DAGR group peer with a normal metric of 48 and a priority metric of
5:
RP/0/(config-if-dagr-peer)# route metric normal 48 priority 5
RP/0/(config-if-dagr-peer)#
show arp
To display the Address Resolution Protocol (ARP), enter the show arp command in .
show arp vrf vrf-name [ip-address | hardware-address | interface-path-id] location node-id
Syntax Description
vrf
(Optional) Specifies VPN routing and forwarding (VRF) instance.
vrf-name
(Optional) VRF instance that identifies a VPN.
ip-address
(Optional) The ARP entries you want to display.
hardware-address
(Optional) The ARP entries that match the 48-bit MAC address are displayed.
interface- path-id
(Optional) Either a physical interface instance or a virtual interface instance as
follows:
• Physical interface instance. Naming notation is rack/slot/module/port and a
slash between values is required as part of the notation.
◦rack: Chassis number of the rack.
◦slot: Physical slot number of the modular services card or line card.
◦module: Module number. A physical layer interface module (PLIM) is
always 0.
◦port: Physical port number of the interface.
• Virtual interface instance. Number range varies depending on interface type.
For more information about the syntax for the router, use the question mark (?)
online help function.
location node-id
(Optional) Displays the ARP entry for a specific location. The node-id argument
is entered in the rack/slot/module notation.
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ARP Commands
show arp
Command Default
The active RSP is the default location.
Command Modes
Command History
Usage Guidelines
Release
Modification
Release 6.0
This command was introduced.
ARP establishes correspondences between network addresses (an IP address, for example) and Ethernet
hardware addresses. A record of each correspondence is kept in a cache for a predetermined amount of time
and then discarded.
For show arp interface-type interface-instance form, the location node-id keyword and argument is mandatory
for Bundle and VLAN-on-Bundle interfaces to indicate which location the cache entries for the bundle should
be displayed. For physical interfaces, specifying the location node-id keyword and argument is optional since
the interface can only exist on one node.
Task ID
Task ID
Operations
cef
read
The following is sample output from the show arp command with no location specified:
RP/0/# show arp
0/7/CPU0
------------------------------------------------------------------------------Address
Age
Hardware Addr
State
Type
Interface
33.1.1.2
e4c7.2284.f863
Interface ARPA
TenGigE0/7/0/3
34.1.1.2
e4c7.2284.f863
Interface ARPA
TenGigE0/7/0/3.1
65.79.1.1
e4c7.2284.f887
Interface ARPA
TenGigE0/7/0/39
------------------------------------------------------------------------------0/RP0/CPU0
------------------------------------------------------------------------------Address
Age
Hardware Addr
State
Type
Interface
12.1.24.208
00:00:03 0016.9cf2.3800
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.0.1
00:53:00 0000.0c07.ac07
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.0.2
00:00:01 0026.0bdd.0000
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.0.3
00:00:05 0026.0bdc.ffc0
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.13.2
02:41:25 0015.17d6.684b
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.36.19
00:33:28 0014.a841.0ffc
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.44.1
00:54:57 6c20.5618.96aa
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.44.2
01:46:47 6c20.5618.982e
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.44.3
02:46:28 4c4e.35b6.57e8
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.44.100
02:45:10 4c4e.35b6.57e8
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.44.101
02:45:05 6c20.5618.96aa
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.49.41
00:03:16 6400.f142.134c
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.49.43
01:10:36 6400.f142.134c
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.49.121
02:54:42 0020.b007.6700
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.49.122
01:51:05 0020.b007.6700
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.49.123
00:31:59 0033.b515.68ff
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
12.7.49.254
00:24:09 0003.310a.a039
Dynamic
ARPA MgmtEth0/RP0/CPU0/0
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ARP Commands
show arp
12.7.54.10
12.7.54.11
12.7.54.12
12.7.57.1
12.7.57.2
12.7.57.8
12.7.57.9
12.7.57.10
12.7.57.11
12.7.57.13
01:24:34
00:06:21
00:05:58
01:59:01
00:54:16
01:25:07
00:59:03
00:22:16
e050.07fa.ef05
e050.07fa.ef05
4c4e.35b6.4af8
10f3.11b6.c634
6400.f142.1500
0024.c4d8.c2cc
6400.f142.0bbe
6400.f142.115a
0022.56d8.36a0
000a.b8b7.fff8
Interface
Interface
Dynamic
Dynamic
Dynamic
Dynamic
Dynamic
Dynamic
Dynamic
Dynamic
ARPA
ARPA
ARPA
ARPA
ARPA
ARPA
ARPA
ARPA
ARPA
ARPA
MgmtEth0/RP0/CPU0/0
MgmtEth0/RP0/CPU0/0
MgmtEth0/RP0/CPU0/0
MgmtEth0/RP0/CPU0/0
MgmtEth0/RP0/CPU0/0
MgmtEth0/RP0/CPU0/0
MgmtEth0/RP0/CPU0/0
MgmtEth0/RP0/CPU0/0
MgmtEth0/RP0/CPU0/0
MgmtEth0/RP0/CPU0/0
The following is sample output from the show arp command with the interface-type interface-instance
argument:
RRP/0/# show arp tenGigE 0/0/0/1
------------------------------------------------------------------------------0/RP0/CPU0
------------------------------------------------------------------------------Address
Age
Hardware Addr
State
Type Interface
20.30.1.1
c472.95a6.2a86 Interface ARPA TenGigE0/0/0/1
20.30.1.2
00:04:58
6c9c.ed2c.a060 Dynamic
ARPA TenGigE0/0/0/1
RRP/0/# show arp mgmtEth 0/RP1/CPU0/0
Address
10.4.9.2
10.4.9.1
10.4.9.99
10.4.9.199
Age
00:35:55
00:35:55
00:49:12
-
Hardware Addr
0030.7131.abfc
0000.0c07.ac24
0007.ebea.44d0
0001.c9eb.dffe
State
Dynamic
Dynamic
Dynamic
Interface
Type
ARPA
ARPA
ARPA
ARPA
Interface
MgmtEth0/RP1/CPU0/0
MgmtEth0/RP1/CPU0/0
MgmtEth0/RP1/CPU0/0
MgmtEth0/RP1/CPU0/0
The following is sample output from the show arp command with the hardware-address designation:
RP/0/# show arp 0005.5f1d.8100
Address Age Hardware Addr State Type Interface
172.16.7.2 - 0005.5f1d.8100 Interface ARPA HundredGigE0/0/0/2
The following is sample output from the show arp command with the location keyword and node-id
argument:
RP/0/# show arp location 0/2/CPU0
Address Age Hardware Addr State Type Interface
192.168.15.1 - 00dd.00ee.00ff Alias ARPA
192.168.13.1 - 00aa.00bb.00cc Static ARPA
172.16.7.1 00:35:49 0002.fc0e.9600 Dynamic ARPA HundredGigE0/1/0/2
172.16.7.2 - 0005.5f1d.8100 Interface ARPA HundredGigE0/1/0/2
This table describes the significant fields shown in the display.
Table 1: show arp Command Field Descriptions
Field
Description
Address
Displays the network address that corresponds to the
hardware address.
Age
Displays the age in hours:minutes:seconds of the
cache entry. A hyphen (-) means the address is local.
Hardware Addr
Displays the LAN hardware address of a MAC
address that corresponds to the network address.
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ARP Commands
show arp traffic
Field
Description
State
Displays the current state of the cache entry. Values
are:
• Dynamic
• Interface
• Alias
• Static
• “-” (indicates global static and alias entries)
Type
Displays the encapsulation type the Cisco IOS XR
software is using for the network address in this entry.
Value is ARPA.
Interface
Displays the interface associated with this network
address.
ARP statistics
Displays ARP packet and error statistics.
ARP cache
Displays general information about the IP address
and MAC address association entries in the ARP
cache.
IP Packet drop count for node */*/*
Displays the number of IP packets dropped because
the buffer ran out of space before an ARP response
was received.
Note
*/*/* represents the node ID in the format
rack/slot/module.
show arp traffic
To display Address Resolution Protocol (ARP) traffic statistics, enter the show arp traffic command in .
show arp traffic [vrf vrf-name] [ interface-path-id ] [location node-id]
Syntax Description
vrf
(Optional) Specifies VPN routing and forwarding (VRF) instance.
vrf-name
(Optional) VRF instance that identifies a VPN.
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ARP Commands
show arp traffic
interface- path-id
(Optional) Either a physical interface instance or a virtual interface instance as follows:
• Physical interface instance. Naming notation is rack/slot/module/port and a slash
between values is required as part of the notation.
◦rack: Chassis number of the rack.
◦slot: Physical slot number of the modular services card or line card.
◦module: Module number. A physical layer interface module (PLIM) is
always 0.
◦port: Physical port number of the interface.
• Virtual interface instance. Number range varies depending on interface type.
For more information about the syntax for the router, use the question mark (?) online
help function.
location node-id
Command Default
(Optional) Displays the ARP entry for a specific location. The node-id argument is
entered in the rack/slot/module notation.
The active RSP is the default location.
Command Modes
Command History
Usage Guidelines
Release
Modification
Release 6.0
This command was introduced.
ARP establishes correspondences between network addresses (an IP address, for example) and Ethernet
hardware addresses. A record of each correspondence is kept in a cache for a predetermined amount of time
and then discarded.
For show arp traffic, interface-instance, the locationnode-id keyword and argument is mandatory for Bundle
and VLAN-on-Bundle interfaces to indicate which location the cache entries for the bundle should be displayed.
For physical interfaces, specifying the location node-id keyword and argument is optional since the interface
can only exist on one node.
Task ID
Task ID
Operations
cef
read
The following is sample output from the show arp traffic command:
RP/0/# show arp traffic
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
17
ARP Commands
show arp traffic
show arp traffic
Thu Dec 10 09:51:38.761 UTC
------------------------------------------------------------------------------0/6/CPU0
------------------------------------------------------------------------------ARP statistics:
Recv: 163 requests, 79 replies
Sent: 14138 requests, 177 replies (0 proxy, 0 local proxy, 14 gratuitous)
Resolve requests rcvd: 7204
Resolve requests dropped: 295
Errors: 0 out of memory, 0 no buffers, 0 out of sunbet
ARP cache:
Total ARP entries in cache: 22
Dynamic: 11, Interface: 11, Standby: 0
Alias: 0,
Static: 0,
DHCP: 0
IP Packet drop count for node 0/6/CPU0: 6909
Total ARP-IDB:19
------------------------------------------------------------------------------0/2/CPU0
------------------------------------------------------------------------------ARP statistics:
Recv: 162532 requests, 243 replies
Sent: 15879 requests, 162561 replies (0 proxy, 0 local proxy, 29 gratuitous)
Resolve requests rcvd: 47593
Resolve requests dropped: 0
Errors: 0 out of memory, 0 no buffers, 0 out of sunbet
ARP cache:
Total ARP entries in cache: 125
Dynamic: 112, Interface: 13, Standby: 0
Alias: 0,
Static: 0,
DHCP: 0
IP Packet drop count for node 0/2/CPU0: 44804
Total ARP-IDB:13
The following is sample output from the show arp traffic command with the location keyword and node-id
argument:
RP/0/# show arp traffic location 0/4/CPU0
Thu Dec 10 09:51:56.209 UTC
ARP statistics:
Recv: 364474 requests, 96 replies
Sent: 14131 requests, 364499 replies (0 proxy, 0 local proxy, 25 gratuitous)
Resolve requests rcvd: 5699
Resolve requests dropped: 94
Errors: 0 out of memory, 0 no buffers, 0 out of sunbet
ARP cache:
Total ARP entries in cache: 18
Dynamic: 9, Interface: 9, Standby: 0
Alias: 0,
Static: 0,
DHCP: 0
IP Packet drop count for node 0/4/CPU0: 5603
Total ARP-IDB:18
IP Addresses and Services Command Reference for Cisco NCS 5500 Series and NCS 540 Series Routers
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