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

[BrandonC]

Hi Elie,

You should be able to do this with a routing policy. See the link below for syntax details:
http://documentation.extremenetworks.com/exos_22.2/EXOS_21_1/Routing_Policies/r_routing-policy-file-...

For example, you could do:entry ip_entry { if match any { nlri 66.133.0.0/23 exact; nlri 66.133.0.2/23 exact; } then { deny; } }

[Elie_Raad]

Hi Brandon, i advertised these 2 prefixes 66.133.0.0/23 66.133.2.0/23 on the primary router connected to the primary ISP . i used the policy written above to block these 2 routes from being advertised to the standby router that i connected to the secondary ISP . the router said . Error: Failed to read policy file AS1187_OUT

can you please advice ?
thank you,
elie

[Elie_Raad]

Thank You Brandon .

[BrandonC]

That's correct. Just make sure to use 'if match any' for the entries with multiple of the same match conditions.

[Elie_Raad]

so the End Result for only denying the 66 and allow all others would be something like this :
configure bgp neighbor 30.119.210.6 route-policy out AS1187_OUT

edit policy AS1187_OUT
entry TOEXP{
if match {
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{
permit;
}
}

Please, correct me if I am wrong .
thank you very much for your help