Redistribution issue between two routing protocol

In this case, customer only performs simple redistribution without any
route protection feature. Suboptimal route occurred which resulted in network
unreachable.

To improve this situation, we use filter policy to filter the OSPF
external route at another switch in ISIS.

Two switch configuration:

Isis

Filter-policy ip-prefix filter import

Ip ip-prefix filter deny 192.168.1.0 24

Ip ip-prefix filter permit 0.0.0.0 0 less-equal 32<?xml:namespace prefix = "o" />