Configuration Guide

Table Of Contents
VSP 9000 or 4000/7200/8000 prior to release 5.0 – redistribution of ISIS into OSPF and vise-
versa
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October 2021
122
Please note the following:
By default, when redistributing OSPF routes into ISIS, all ISIS switches with IP Shortcuts enabled
will always use the internal metric with the SPBM cost
o
lower cost preferred, to the BEB nodes advertising the redistributed routes
o
If equal, use the prefix cost (external metric) with lower cost preferred and if prefix cost is
the same, the routes are considered ECMP routes
Instead of using the default internal metric, the ISIS metric type of external can be used as per
the next example and is the preferred method for the VSP 4000/7200/8000 as of release 5.0
configure terminal
no ip alternative-route
route-map "reject" 1
no permit
enable
exit
router ospf
as-boundary-router enable
redistribute isis
redistribute isis enable
exit
router isis
accept adv-rtr 0.90.01
accept adv-rtr 0.90.01 route-map "reject"
accept adv-rtr 0.90.01 enable
redistribute ospf
redistribute ospf enable
exit
isis apply accept
isis apply redistribute ospf
ip ospf apply redistribute isis
configure terminal
no ip alternative-route
route-map "reject" 1
no permit
enable
exit
router ospf
as-boundary-router enable
redistribute isis
redistribute isis enable
exit
router isis
accept adv-rtr 0.90.02
accept adv-rtr 0.90.02 route-map "reject"
accept adv-rtr 0.90.02 enable
redistribute ospf
redistribute ospf enable
exit
isis apply accept
isis apply redistribute ospf
ip ospf apply redistribute isis