System information

Configuring Routing Policy
7-13
tag is a unique name for routing process.
route-map indicates current routing protocol.
match internal indicates routes that are internal to an AS.
external 1 indicates routes that are external to an AS, but are imported into OSPF
as either Type 1 or Type 2 external route.
external 2 indicates routes that are external to an AS, but are imported into OSPF
as a Type 2 external route.
metric indicates the source protocol from which routes are being redistributed;
valid values are BGP, connected, RIP OSPF and static.
Example
This example redistributes routes learned from OSPF into BGP. The commands
enable BPP, specify the autonomous system 100, and specify OSPF as the protocol
type for the redistribution.
router bgp 100
redistribute ospf
Applying a Damping Criteria
Route flapping occurs when a link constantly fluctuates between being available and
unavailable. Every time a link changes its availability, the upstream neighbor sends an
update message to all its neighbors. These routes are advertised globally. This process
continues until the underlying problem is fixed.
Route flap damping minimizes instability caused by route flapping. Use policy-based
route flap damping to apply the following damping criteria to specific routes: