Hello,
in this thread http://forum.mikrotik.com/t/bgp-med-attribute-and-ibgp/64343/1 a mikrotik employee writes that MED is only taken into account when the neighboring AS in AS_PATH is equal.
Is there any other solution to prefer a bgp route if weight local_pref and AS_PATH length is equal? AFAIK is cisco, brocade and juniper doing it with local MED even if the neighboring AS in AS_PATH is NOT equal as long as the AS_PATH length is the same.
Regards,
Michael
Prepending or Communities can give you the option to prefer a specific patch inbound across different AS peers.
You can also attempt to write a script to approximate conditional BGP advertisements (cisco BGP feature) which guarantees traffic will come in on a certain path.
Hello,
thanks for your reply and your suggestions. It’s a bit sad that this does not work on routeOS as this is working on all other routers I know.
I will try your suggestions.
Regards,
Michael
As far as I can find Cisco works exactly the same way as RouterOS.
http://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/13759-37.html
Please provide configuration example or link to document which states otherwise.
MED is an optional non-transitive attribute so it is not passed (say) from AS #1 by AS #2 to AS #3. Thus it would not really make sense to interpret and act on MED values from two distinct AS sources in eBGP. Thus the restriction mentioned in the thread you quoted. The same restriction applies for eBGP on Cisco routers.