Adding to the code above

my %downserver = ();
if (...) {
   my $server = $1;
   if (!exists $downserver{$server}) {
       $downserver{$server} = "Restarting $server";
       run start server command
   }
}
[download]

or you could maintain the list and process at the end.

my %downserver = ();
if (...) {
   my $server = $1;
   my $downtime = $n;        # some other extracted bit from regex
   $downserver{$server} = $downtime;
}

foreach my $server (keys %downserver) {
    if ($downserver{$server) down after last run) {
        run start server
        write to log server upped
    }
}
[download]