Close; you need a negative look-behind assertion: 
#!/usr/bin/perl
use strict;
use warnings;

my $var = "use neighbor 2001:504:0:4::6181:1";
($var =~/(?<!use )neighbor[[:alpha:]-]* ([[:alnum:]\.-:]+)/) and do{
    print $1;
};

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#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: Quick Regex trouble by kennethk
in thread Quick Regex trouble by jrvd

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