Can I advertise ibgp route to ebgp peer?

[syjeon]

Dear.

Just I wanna to check whether it is possible to check the following things.

we have a two cisco router which is connected IBGP peer, and exchange routing with IBGP route-reflect, so they share the routing protocol with IBGP.

but, regarding project, we have to advertise ibgp route which is learned from ibgp peer to eBGP peer to advertise inside network.

in this case, is there no any other configuratione except state neighbor to ebgp? just we make neighbor with eBGP peer , and there is no need to add network command in bgp?

just I need to checkup this things. just thing I want to know is that It can be advertise route which is learned by IBGP to eBGP peer? except no any configuration except neighbor announce in BGP.

[Giuseppe Larosa]

Hello Syeion,

from a direct iBGP session yes you can advertise to an eBGP peer with no special commands

Hope to help

Giuseppe

[oyama.hall]

Yes.

You can as long as the routes that you are advertising to your eBGP neighbor are publicly reachable.

IP Space as defined in RFC 1918 & 4193 should not be advertised...as the ISP router should be dropping it anyways.

The network command is needed. A route to the iBGP network is needed on the edge router if there is no directly connected interface or route on the router as well. If not, the route will not appear in the BGP routes to be advertised.

Cheers!

[lacirasella]

Hi,

be sure that prefix doesn't have the BGP attribute no-export or no-advertise