On Sep 25, 2011, at 3:37 AM, Tom Storey <tom@snnap.net> wrote:
I found I had to do this many years ago on some Cisco routers to get them to load balance (per packet) across two links. Adding 0.0.0.0/0 routes across both links just resulted in traffic routing across one link. Broke it into two /1's per link and it worked perfectly.
Two other reasons for this too: 1) Something won't redistribute 0.0.0.0/0 on the network. Either because the person doesn't know the command to tell the router to do it, or because the router simply won't redistribute a default route. 2) Could also be failover. One router might be advertising 0.0.0.0/0 on one end of the network. A different router on a different part of the network might be advertising the two /1's. The /1's would be used unless they became unreachable.