10-22-2014 05:42 AM
Hi i have 2ISP Providers via BGP create 2 Prefix List and have 4 Networks slesh /24. My questions is how i can set when i add one network on 1st prefixlist i want to be use for out my second ISP couse when i use for now i try with traceroute google.com (example) but my out is First ISP..
10-23-2014 05:53 AM
If i understand the question the answer is simple. You want to advertise out both isp but only want traffic to go out isp A and not ISP B?
If thats the case you can create you 2 prefix lists or even use the same prefix list for advertisements ie.
local-as "myas num"
neighbor 18.104.22.168 remote-as x.x.x.x
neighbor 22.214.171.124 remote-as y.y.y.y
neighbor 126.96.36.199 prefix-list my-prefixes out
neighbor 188.8.131.52 prefix-list my-prefixes out
you can then just set the localpref on isp b to a lower value
ie route-map LOCALPREF PERMIT 10
SET LOCAL-PREFERNCE 90
NEIGHBOR 184.108.40.206 ROUTE-MAP OUT LOCALPREF
Now traffic will only go out isp a unless isp a is down.