my $hostname   = 'db71b.pair.com';
my $dbase      = '111';
my $mysql_user = '222';
my $mysql_pass = '333';

my $dbh = DBI->connect(
    "DBI:mysql:$dbase:$hostname",
    $mysql_user,
    $mysql_pass,
    {
        RaiseError => 1,
        AutoCommit => 0
    }
) || die "DB connection failed: $DBI::errstr\n";

# DB connection is successful if we are here ...
[download]

Update: fixed wrong usage of $host/$hostname.