Thank you for the feedback. I was aware of disabling aspath loop detection, but have not yet explored it; based on my reading, it seemed like a hacky workaround. Are there any drawbacks to this approach, aside from the obvious possibility of creating loops? With regard to an IBGP mesh, it seems that if a BGP session in my mesh fails, routing of prefixes between the affected routers fails. Is this the expected behavior? Is this where I should be using an IGP to route around the failed IBGP? Thanks! On Mon, Sep 1, 2014 at 11:54 AM, Raphael Mazelier <raph@futomaki.net> wrote:
Le 30/08/2014 01:36, Tom Daly a écrit :
Hi, It sounds like you might want to try disabling aspath loop detection for eBGP. Checkout the bird option called "allow local as [number]" as documented at http://bird.network.cz/?get_doc&f=bird-6.html#ss6.2. This will allow you to import prefixes with your own ASN in the aspath.
However, one possible pitfall is that your upstream ISP's router might try to be smart - and not send prefixes with your aspath in them too. Older Foundry boxes do this and there is a per BGP peer knob you have to turn.
Overall, this should let you run everything over eBGP and run two simple island networks.
Cheers, Tom
Unfortunately proper ISPs make their job good and does not advertise your own route. I have a Pop in the same configuration of yours. Two solution : IBGP in a GRE tunnel, it's uggly, but It works. Or static route :)
-- Raphael Mazelier AS39605