Internet routers BGP / OSPF config

[carl_townshend]

Hi all

Can anyone confirm or help me to see how our internet routers are set up

We currently have 2 internet routers both on different ISP's

we receive a default route on both, these routers then connect to some internal routers using OSPF which advertises our PI address range.

1 internet router is active, the other is currently in standby both in and out

I asked the consultant how they are set up for resilience, the reply was         

"the backup internet router just learns the route from the first – if it sees the route in the table it doesn’t advertise it itself out to the internet"

what does thsi mean and how would you think it is set up ?

cheers

[Pedro Lereno]

Hi Carl,

I think the backup router has an ibgp connection to the active one, has a lower local-preference to its wan link (outbound traffic) and advertises your ip address space with as-path prepending or some communities agreed with the ISP (inbound traffic).

You can check this video for local preference and as-path prepend: http://youtu.be/DVT1y1oSLUs

And this for bgp communities: http://youtu.be/xVQlYPWOCYE

Regards,

Pedro Lereno