On Tue, 17 Aug 2010 12:11:56 +0000 (UTC) Sven Olaf Kamphuis <sven@cb3rob.net> wrote:
nowadays, i'd simply put them all on the same /24 which you simply announce on different pops
I would raise a red flag of caution with this approach especially for services that need to be reachable outside your network If there is a a snafu with said /24 prefix, particularly outside your own routing domain, a reachability problem could persist for an extended period and you'd be in a difficult position to solve it on your own. For instance, if it flaps and someone, for better or worse, dampens that route, that could mean an extended outage for all those hosts until the damping period timer expires. On a related note, some systems and folks have taken multiple unique origin ASNs as a measure of diversity. In pratice, unless there is some odd AS path mangling going on for your specific routes, which is unlikely, one can properly instrument diversity using a single origin ASN with multiple prefixes. Its the path and the prefix that matters, much less the ASN. John