I am trying to use variables to hold the regex exppression to make it easier to code, and I'm running into one issue parsing firewall logs.

When I call the same regex variable multiple times the first group returns the correct result but the second one shows part of the first IP address.

-- Sample data Mar 10 07:42:38 DR-FW-1 : %ASA-6-305011: Built dynamic UDP translation from inside:172.28.17.130/3324 to outside(internet-traffic):69.176.102.83/24295

output: 
re1  ->  172.28.17.130
re2  ->  17.

------------------------------------------

my $Raw_Log = "";
my $re_ipv4 = qr/(([2]([0-4][0-9]|[5][0-5])|[0-1]?[0-9]?[0-9])[.]){3}(
+([2]([0-4][0-9]|[5][0-5])|[0-1]?[0-9]?[0-9]))/;
# Open file to read lines
my $logfile = $ARGV[0];
my $linenum = 0;

open(LOGFILEHD, $logfile);

while( <LOGFILEHD>){
   $Raw_Log = $_;
   print "$Raw_Log\n";
   $Raw_Log =~ /($re_ipv4).*($re_ipv4)/;

   print "re1  ->  $1\n";
   print "re2  ->  $2\n";

   $linenum  += 1;
}
close(LOGFILEHD);

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In reply to Using variable to hold regex expression by salatconed

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