it's a simple approach i'm sure, not too confident how even it'd be, unless you start looking to remove common parts of fqdn's... i.e. "w" would cover maybe 75% of all domains requested, as they'd start with www. would be a lot less cpu overhead that generating md5 sums with each [HTTP::host] though, and i'm not after any real load balancing really, just some notional active / active setup that isn't wasteful.
you felt the persistence hashes also came up short? i guess that there's logic that once a domain gets sent to a box based on current generic observed LB rules, for example, it'll always go that way, and if load increases on that particular proxy, subsequent domains would be permanenetly pushed to the other box... food for thought certainly. thanks.