TMTOWTDI, this way with a slice:

open (LOG, "$fw_logfile") or die and mail_error($!);
open (OUTFILE, "+>>$outfile") or die and mail_error($!);
 
my $seen = 0;
 
while(<LOG>){
  foreach my $i (@newips[0..499]){
    print OUTFILE if (/\;drop;[^"]*$i/) && $seen++;
  }
}
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