Cisco ASR 1000 Configuration Guide

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Cisco ASR 1000 Series Aggregation Services Routers SIP and SPA Software Configuration Guide
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Chapter 13 Configuring the POS SPAs
Configuration Tasks
Modifying the Keepalive Interval
When the keepalive feature is enabled, a keepalive packet is sent at the specified time interval to keep
the interface active. The keepalive interval must be configured to be the same on both ends of the POS
link.
To modify the keepalive interval, use the following command in interface configuration mode:
To disable keepalive packets, use the no form of this command.
Note If keepalives are enabled and you are trying to configure line loopback on a POS interface, the keepalive
protocol will fail and periodically reset the interface based on the keepalive timeout and cause Layer 1
errors on the other end of the link that is trying to do the loopbacks.
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You can avoid this by using the no keepalive command on the POS interface that is configured for line
loopback. The side that is not in line loopback detects that its keepalive is being looped back and
functions properly. An interface configured for internal loopback also functions properly with keepalives
enabled.
Verifying the Keepalive Interval
To verify the keepalive interval, use the show interfaces pos privileged EXEC command and observe
the value shown in the “Keepalive” field.
The following example shows that keepalive is enabled for interface port 0 on the POS SPA installed in
subslto 0 of the SIP that is located in chassis slot 2 of the Cisco ASR 1000 Series Router:
Router# show interfaces pos 2/0/0
POS2/0/0 is up, line protocol is up
Hardware is Packet over Sonet
Internet address is 10.1.1.1.2
MTU 9216 bytes, BW 622000 Kbit, DLY 100 usec, reliability 255/255, txload 1/255,
rxload 1/255
Keepalive set (10 sec)
Command Purpose
Router(config-if)# keepalive [period [retries]] Specifies the frequency at which the Cisco IOS
software sends messages to the other end of the link,
to ensure that a network interface is alive, where:
• period—Specifies the time interval in seconds for
sending keepalive packets. The default is 10
seconds.
• retries—Specifies the number of times that the
device will continue to send keepalive packets
without response before bringing the interface
down. The default is 5 retries.

Cisco ASR 1000 Specifications

General

Brand	Cisco
Model	ASR 1000
Category	Network Router
Language	English