HI,
In the attached diagram from cisco site if we assume R101 and R102 are two DC having a layer 2 link and both are advertising same subnet (eg. 192.168.12.0/24) to the ISP i understand by using BGP metrics we can make one DC primary and other as secondary for this subnet. What i am interested to know if we need to use iBGP between the two routers (R101 and R102) as showing in diagram or we can use eBGP also between them since they are two different locations?
Thanks,