Route Redistribution with Tags
- Tag EIGRP as 100
- TAG OSPF as 1
- Route maps should take the form DENY -> PERMIT.
- Routes are tagged when they are advertised.
Route tags appear on-the-wire and can be read by other routers.
ospf.lsa.asext.extrttag == 100
In this example, EIGRP becomes a Type-5 OSPF update, with a route-tag of 100. If we look for these tags can exclude them in redistribution updates.
route-map RM_OSPF_INTO_EIGRP deny 10
description previously tagged EIGRP traffic
match tag 100
!
route-map RM_OSPF_INTO_EIGRP permit 20
match source-protocol ospf 1
set tag 1
!
route-map RM_EIGRP_INTO_OSPF deny 10
description previously tagged OSPF traffic
match tag 1
!
route-map RM_EIGRP_INTO_OSPF permit 20
match source-protocol eigrp 100
set tag 100
!
router eigrp 100
redistribute ospf 1 metric 1000000 100 255 1 1500 route-map RM_OSPF_INTO_EIGRP
!
router ospf 1
redistribute eigrp 100 subnets route-map RM_EIGRP_INTO_OSPF