#! /usr/bin/perl

$file= "/opt/elasticsearch/logs/elasticsearch.log" ;
$fd_file ;
$line ;
# open ($fd_file, '<:encoding(UTF-8)', $file) or die '<:encoding(UTF-8)', or die "Could not open file '$file' $!" ;

# while (<$fd_file>)

$line = `tail -n 20 $file` ;

if ($line =~ m/[gc][old]/)
{
    print "CRITICAL" ;
    exit(2) ;
}
else
{
    print "OK" ;
    exit(0) ;
}