bgp community: [ Edited ]

[Iglu]

Hi

I have to send a community to one bgp-peer to signalize a backup link.

I have configured a policy-options:  community BGP-BACKUP members xxxx:22450;

but how do i transmit these to my peer. Do I have to configured it in the neigbohr statment?

best regards

IGLU

Message Edited by Iglu on 01-09-2009 08:23 AM

[davidjdv]

Hello,

You would do this within an export policy which can be applied at the neighbor level (or group, or protocol). As am example, here we decide to advertise our aggregates and add your community:

policy-statement send-community {

    from protocol aggregate;

    then {

        community add BGP-BACKUP;

accept; 

    }               

}

More details in the documentation:

 https://www.juniper.net/techpubs/software/junos/junos93/swconfig-policy/configuring-communities.html

HTH,

/david 

[Iglu]

Hi David

How can I be sure that thit community is not send it to both peers (Same ISP two peers connecting to my one router)

Where would be the match in your example that it would send it to the peer.

as you see I'am not an expert in configuring bgp on Junos although I like the junos more and more.

regards

IGLU

[davidjdv]

Hi Iglu,

Glad you like JUNOS  

This is where it is interesting to use the export policy at different levels - you can specify it at the protocol, group or neighbor level (where the most specific definition wins). In this case, you could have something like:

group ebgp {
    type external;
    peer-as 65002;
    neighbor 1.1.1.2 {
        export send-community;
    }
    neighbor 2.2.2.2;
}

This way you only send the community to the first neighbor, not the second.

This is explained further here:

https://www.juniper.net/techpubs/software/junos/junos93/swconfig-routing/applying-routing-policy.htm...

Regards,

/david 

Message Edited by davidjdv on 01-10-2009 01:28 AM