Cisco NCS 5500 Series Configuration Manuals page 40

Configure Nonstop Forwarding for IS-IS
• Enter the cisco keyword to run IS-IS in heterogeneous networks that might not have adjacent NSF-aware networking
devices.
• Enter the ietf keyword to enable IS-IS in homogeneous networks where all adjacent networking devices support
IETF draft-based restartability.
Step 4
nsf interface-expires number
Example:
RP/0/RP0/CPU0:router(config-isis)# nsf interface-expires 1
Configures the number of resends of an acknowledged NSF-restart acknowledgment.
• If the resend limit is reached during the NSF restart, the restart falls back to a cold restart.
Step 5
nsf interface-timer seconds
Example:
RP/0/RP0/CPU0:router(config-isis) nsf interface-timer 15
Configures the number of seconds to wait for each restart acknowledgment.
Step 6
nsf lifetime seconds
Example:
RP/0/RP0/CPU0:router(config-isis)# nsf lifetime 20
Configures the maximum route lifetime following an NSF restart.
• This command should be configured to the length of time required to perform a full NSF restart because it is the
amount of time that the Routing Information Base (RIB) retains the routes during the restart.
• Setting this value too high results in stale routes.
• Setting this value too low could result in routes purged too soon.
Step 7 commit
Step 8
show running-config [ command ]
Example:
RP/0/RP0/CPU0:router# show running-config router isis isp
(Optional) Displays the entire contents of the currently running configuration file or a subset of that file.
• Verify that "nsf" appears in the IS-IS configuration of the NSF-aware device.
• This example shows the contents of the configuration file for the "isp" instance only.
Routing Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.3.x
28
Implementing IS-IS