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Mauricio_Cusine's avatar
Mauricio_Cusine
Icon for Nimbostratus rankNimbostratus
Aug 22, 2007

Validate IP address with regexp

Hello,   I am trying to check if a IP address is valid in the bigip with regexp (I don't know if anybody know other method).     The regexp is the follow but don't work. Anybody can help me?....
application delivery
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Joe_Pruitt's avatar
Joe_Pruitt
Feb 21, 2008
Regexps are not always the best solution. If all you are concerned about is whether the string is in the form of a.b.c.d where a,b,c,d are between 1 and 255 inclusive, how about this solution:

set addr "10.10.10.10"
  
set a [getfield $addr "." 1]
set b [getfield $addr "." 2]
set c [getfield $addr "." 3]
set d [getfield $addr "." 4]
  
if { (1 <= $a) && ($a <= 255) &&
     (1 <= $b) && ($b <= 255) &&
     (1 <= $c) && ($c <= 255) &&
     (1 <= $d) && ($d <= 255) } {
  log local0. "$addr is a valid IP Address"
} else {
  log local0. "$addr is NOT a valid IP Address"
}

This will definitely be less CPU intensive than running the regular expression and should cover all the corner cases.

-Joe