Thursday, February 25, 2021

Does Unequal-Cost Multipathing Make Sense?

Every now and then I’m getting questions along the lines “why doesn’t X support unequal-cost multipathing (UCMP)?” for X in [ OSPF, BGP, IS-IS ].

To set the record straight: BGP does support some rudimentary form of unequal-cost multipathing with the DMZ Bandwidth community, but it only works across multiple egress points from a single autonomous system. Follow-up nerd knobs described how to use the same community over EBGP sessions; not sure whether anyone implemented that part (comments welcome).



source https://blog.ipspace.net/2021/02/does-ucmp-make-sense.html?utm_source=atom_feed

No comments:

Post a Comment