Direct requests based on hashed cookie data

Aren't you just looking for the modulus operator? If all you want is the remainder from the first number divided by the second, you could just use the % operator. In your example, 62 % 12 would return 2. Here's an iRule as a reference.

 

 

when HTTP_REQUEST { 
   set CookieId [HTTP::cookie User_cookie]  
   if { [string is integer $CookieId] } { 
     set PoolId [expr $CookieId % 12 ] 
     set PoolName "Pool_$PoolId"  
      pool $PoolName 
     log "cookieid_rule: CookieId = $CookieId; PoolId = $PoolId; PoolName = $PoolName" 
   } else { 
     log "cookieid_rule: Invalid CookieId - not in integer format!"   
   } 
 }

 

 

By the way, it looks like the floor() math function is not included in our implementation. I'll verify this and post a list of available builtin functions. Your example would likely cause a runtime violation in the iRule producing an error similar to the following:

 

 

syntax error in expression "set TempCookieId2 [expr floor $TempCookieId]": variable references require proceeding $...".

 

 

If you replace your code with floor($TempCookieId) you would get a configuration error stating something like the following:

 

 

unknown math function "floor" while compiling "expr floor($TempCookieId)...

 

 

-Joe