$re = '/^(mm[gvis]([0-9]{1,3})?|((media(\.|-)[a-zA-Z]{1,4}[0-9]{1,2}-[0-9]{1,2}\.)(cdn|fna)))\.whatsapp\.net$/m';
$str = 'mms241.whatsapp.net
mmi362.whatsapp.net
mmv785.whatsapp.net
mmg362.whatsapp.net
mmg.whatsapp.net
media.fada1-1.fna.whatsapp.net
media.faq12-1.fna.whatsapp.net
media.saq1-13.fna.whatsapp.net
media.sif1-2.cdn.whatsapp.net
media.scf21-2.cdn.whatsapp.net
media.sqf1-25.cdn.whatsapp.net
media-scf21-2.cdn.whatsapp.net
media-sqf1-25.cdn.whatsapp.net
media-fawq1-13.fna.whatsapp.net
media.fyei6-5.fna.whatsapp.net';
preg_match_all($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