Create numerous BGP sources with a single router

Sometimes you need numerous BGP sources in your lab, but have only a fixed number of routers. Although you could introduce an extra BGP source with Quagga running on Linux (or use tricks to generate more than one BGP source on a single Linux host), it’s usually best if you could avoid the introduction of extra devices in your lab.

Recent releases of Cisco IOS provide a perfect solution: you can run as many BGP instances as you wish on a single router (each one in its own VRF) and use the BGP Support for Dual-AS Configuration to replace actual AS number with the desired one.

Read the whole article in the CT3 wiki

4 comments:

Anonymous said...

Hi,

IIRC what you can't do (and which was what I needed ofcourse), was to replace the router's AS num, with that of the peer's. i.e. fake iBGP peering with peer instead of eBGP. shame...

/Pete

Ivan Pepelnjak said...

Your memory is perfect. Quagga to the rescue :)

Anonymous said...

Hello Ivan,

Many Cisco docs mention ROUTEM as a BGP speaker and/or client simulator. Do you have more info about it? How is it available?

Thanks, Jon

Ivan Pepelnjak said...

@Jon: I have no information on ROUTEM. It could be an internal testing tool, but I don't see a great need for it (apart from stress testing, but if you're interested in that, you could easily write your own BGP source in PERL).

Ivan Pepelnjak, CCIE#1354, is the chief technology advisor for NIL Data Communications. He has been designing and implementing large-scale data communications networks as well as teaching and writing books about advanced technologies since 1990. See his full profile, contact him or follow @ioshints on Twitter.