help, route tracking and advertising in BGP

[carl_townshend]

Hi

we have 2 internet routers, 1 primary and 1 backup.

I believe that the one of the routers has a route track statement tracking the other router, there is a static route for our address block we own pointing to our next hop inside, if the route track fails the static route is removed and then BGP advertises the route out on the backup router.

Im unsure how they have done this, can anyone shed some light?

cheers

Carl

[adnane dakna]

normally each internet routers receive the same prefix from internet but primary router  advertise routes to IBGP network with greater local preference rather than backup router , with this config  traffic toward internet take primary route , when this primary route fail  network uses routes advertised by backup router (with default local preference)

[carl_townshend]

Hi

we are not using IBGP, Just 2 different ISP's, the routers run ospf on the inside, we redistribute BGP into ospf.

however there is a static route somewhere that tracks a route, if this route is lost the backup router then advertises via BGP our address block to the internet.

can anyone tell me how this would be achieved ?

[milan.kulik]

Hi,

that could be achived by BGP Conditional Advertisement configured on you backup router.

See

http://www.cisco.com/en/US/customer/tech/tk365/technologies_configuration_example09186a0080094309.shtml

for details.

HTH,

Milan