LDP

[amms68958]

As far as I know, in Cisco implementation of LDP ,all IGP routes will be imported to the LDP database ,and the same will be advertised to the LDP neighbours by default. If I have a requirement that only loopbacks are needed to be advertised to the LDP neighbours thruout ,how can I configure a policy for the same .

Thanks in advance,

Thomas.

[mheusinger]

Hi Thomas,

the feature you are looking for is called "conditional advertisement". You can define the networks LDP should advertise a label for with an access-list and also optionally the LDP peers through an access-list. An example config looks like this:

no mpls ldp advertise-tags

mpls ldp advertise-tags for 100 to 11

access-list 100 permit ip 192.168.1.0 0.0.0.255 host 255.255.255.255

access-list 11 permit host 10.1.1.1

access-list 11 permit host 10.1.1.2

access-list 11 permit host 10.3.4.5

where f.e. host routes from 192.168.1.0/24 are your loopbacks and there are three peers 10.x.x.x.

Hope this helps! Please rate all posts.

Regards, Martin

[olorunloba]

Just an addition to Martin's post. If you want that conditional advertisement for all LDP neighbors, then omit the access list for the host i.e. the Martin's config can be

no mpls ldp advertise-tags

mpls ldp advertise-tags for 100

access-list 100 permit ip 192.168.1.0 0.0.0.255 host 255.255.255.255