How random is rand()?

A solution I've come up with is to use a STATS profile.

 

Then for every connection (on every vhost) we can increment a counter. The code snippet then becomes

 

 

 
   set iruleversion [format "%04X" 1] 
   set F5id "[format "%02X" 1]" 
   STATS::incr Booking_stats request_count 
   set rnum [format "%08X" [STATS::get Booking_stats request_count] ] 
   set cthash [format "%08X" [clock seconds] ] 
   set tracker "$F5id$iruleversion$cthash$rnum" 
 

 

 

This allows us to identify the BigIP pair (F5id) the request was processed by, and gives us a version number (iruleversion) for the iRule, which together with the clock should ensure we don't get duplicate values if/when the Booking_stats profile is reset.

 

Unfortunately the F5id and iruleversion need manual control, but as I don't think we'll be updating either frequently this isn't a problem.

 

 

Rob