Implementing IS-IS on Cisco IOS XR Software
How to Implement IS-IS on CiscoIOS XR Software
RC-286
Cisco IOS XR Routing Configuration Guide
OL-14356-01
DETAILED STEPS
Command or Action Purpose
Step1 configure
Example:
RP/0/RP0/CPU0:router# configure
Enters global configuration mode.
Step2 router isis instance-id
Example:
RP/0/RP0/CPU0:router(config)# router isis isp
Enables IS-IS routing for the specified routing instance, and
places the router in router configuration mode.
•You can change the level of routing to be performed by
a particular routing instance by using the is-type router
configuration command.
Step3 lsp-refresh-interval seconds [level {1 | 2}]
Example:
RP/0/RP0/CPU0:router(config-isis)#
lsp-refresh-interval 10800
(Optional) Sets the time between regeneration of LSPs that
contain different sequence numbers
•The refresh interval should always be set lower than the
max-lsp-lifetime command.
Step4 lsp-check-interval seconds [level {1 | 2}]
Example:
RP/0/RP0/CPU0:router(config-isis)#
lsp-check-interval 240
(Optional) Configures the time between periodic checks of
the entire database to validate the checksums of the LSPs in
the database.
•This operation is costly in terms of CPU and so should
be configured to occur infrequently.
Step5 lsp-gen-interval {[initial-wait initial |
secondary-wait secondary | maximum-wait
maximum] ...} [level {1 | 2}]
Example:
RP/0/RP0/CPU0:router(config-isis)#
lsp-gen-interval maximum-wait 15 initial-wait 5
(Optional) Reduces the rate of LSP generation during
periods of instability in the network. Helps reduce the CPU
load on the router and number of LSP transmissions to its
IS-IS neighbors.
•During prolonged periods of network instability,
repeated recalculation of LSPs can cause an increased
CPU load on the local router. Further, the flooding of
these recalculated LSPs to the other Intermediate
Systems in the network causes increased traffic and can
result in other routers having to spend more time
running route calculations.
Step6 lsp-mtu bytes [level {1 | 2}]
Example:
RP/0/RP0/CPU0:router(config-isis)# lsp-mtu 1300
(Optional) Sets the maximum transmission unit (MTU) size
of LSPs.
Step7 max-lsp-lifetime seconds [level {1 | 2}]
Example:
RP/0/RP0/CPU0:router(config-isis)#
max-lsp-lifetime 11000
(Optional) Sets the initial lifetime given to an LSP
originated by the router.
•This is the amount of time that the LSP persists in the
database of a neighbor unless the LSP is regenerated or
refreshed.