$re = '/In:.+\(([0-9\.]+%)\).+Out:.+\(([0-9\.]+%)/m';
$str = '["XXXXXXX"], (up), MAC: XX:XX:XX:XX:XX:XX, Speed: 2 GBit/s, In: 0 Bit/s (0%), Out: 6.53 GBit/s (warn/crit at 1.6 GBit/s/1.8 GBit/s) (326.45%)(!!)
["XXXXXXX"], (up), MAC: XX:XX:XX:XX:XX:XX, Speed: 2 GBit/s, In: 0 Bit/s (warn/crit at 1.6 GBit/s/1.8 GBit/s) (95.45%), Out: 6.53 GBit/s (32.00%)(!!)';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php