Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Community Member

BGP route map question

Hi,

I came across a route-map statement on the config. of router A peering through EBGP to router B.

!

neighbor <router B's IP> route-map

PREF in

!

route-map PREF permit 10

match community 10

set local-preference 110

!

route-map PREF permit 20

match community 20

set local-preference 120

!

route-map PREF permit 30

!

My question concerns the need for the last permit statement. What is the default action in route maps when no match and/or set actions are specified?

Thanks,

Rajesh

3 REPLIES
Bronze

Re: BGP route map question

Hi,

the third statement will assign a local pref of 100 (default) to all prefixes which will not have a community set to 10 or 20.

Default local pref see:

http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094431.shtml

If you do not have the last permit statement it would simply ignore all prefixes without a community of either 10 or 20.

Hope that helps

Roger

Community Member

Re: BGP route map question

Roger,

Thanks. Without the last permit statement, would

all other prefixes be dropped or simply ignored and

passed through?

Assuming router A is running IBGP with other

routers in its AS, wouldn't it advertise EBGP

learned prefixes to IBGP peers with default

local-pref value of 100 anyway?

Rajesh

Bronze

Re: BGP route map question

Hi Rajesh,

without the last permit statement the prefixes will be ignored/dropped and not passed through.

so in the sample you give the answer is no....the router would not accept it and because of this not advertise this prefixes.

regards

roger

215
Views
0
Helpful
3
Replies
CreatePlease to create content