deny specific prefixes in bgp

[Elie_Raad]

Hi,
i am trying to deny exact prefixes 66.133.0.0/23 and 66.133.2.0/23 from being advertised and allow everyhting else to an iBGP neighbor (214.63.21.4) the configuration should be done on 214.63.21.3. using a neighbor route-policy command.

Neighbor 214.63.21.3 is connected to neighbor 214.63.21.4.

can someone help .
thank you,
elie

[Jarek]

Elie,

what EXOS you have on those switches ?

Maybe you are facing: https://gtacknowledge.extremenetworks.com/articles/Solution/Switch-reboots-with-EPM-application-wdg-...

--
Jarek

[Elie_Raad]

hi Nick,
can you please explain to me what this route-policy do when applied to a bgp neighbor out
entry TOEXP{
if match all {
nlri 66.133.0.0/23 exact;
nlri 66.133.2.0/23 exact;
}then{
deny;
}
}
entry TOEXP1{
if match any{
nlri 0.0.0.0/0;
}then{
}
}
. once i applied this config on the primary bgp router out toward the standby router the Switch reboots with EPM application wdg timer warning messages and the rtmgr process memory went high

[Nick_Yakimenko]

in fact, without exact keyword you may filter out only 66.133.0.0/22
that will filter all specific announces of your inetnum 66.133.0.0-66.133.3.254 from a /22 to a /32

[Nick_Yakimenko]

First you create policy

edit policy bgp-out

An editor based on vi will be opened (press i to edit, ESC to stop editing, then type :wq to exit

Enter following

entry bgp-out-00 {if match any {
nlri 66.133.0.0/23;
nlri 66.133.2.0/23; }
then {
deny ;
}
}

Then you apply the policy to a neighbor:

configure bgp neighbor 214.63.21.4 route-policy out bgp-out

if you ever after edit the policy, you may refresh changes issuing the command

refresh policy bgp-out

[Elie_Raad]

Thank You Nick