How's this:

#!/usr/local/bin/perl -w
use strict;
my $log="192.168.1.254 was around";
my $ip="192.168.1.254";
my @ip;
push @ip,($log =~ /(^\Q$ip\E.*$)/);
print @ip;
__END__
192.168.1.254 was around
[download]

Update: Added ^ anchor, poster wanted IP at start of string.

CU
Robartes-