Bypassing a VIP based on destination address

Thanks for the explanation Hamish.

One final question...How do I update the iRule so it matches on the following pattern: webmail.*.server.com. This is because schools connect to our

webmail system using their own domain name - eg: http://webmail.school123.server.com

I've tried various permutations to include the the regex to match only letters {^[A-Za-z]+$} within the iRule but keep getting errors. How do I place the

regex wildcard into the iRule.

if { ([HTTP::uri] contains "webamil.*.server.com") || ([HTTP::header host] equals "webmail.*.server.com") }

Thanks.

Andy