librenms-librenms/includes/polling/os/symbol.inc.php

<?php

$fnSysVersion = snmp_get($device, '.1.3.6.1.4.1.388.11.2.2.1.3.2.0', '-Ovq');
$serial       = trim(snmp_get($device, '.1.3.6.1.4.1.388.11.2.2.1.1.0', '-Ovq'), '"');
$version      = trim(snmp_get($device, '.1.3.6.1.4.1.388.11.2.2.1.3.2.0', '-Ovq'), '"');
// preg_match("/HW=(^\s]+)/",$sysDescr,$hardwarematches);
preg_match('/\s+[^\s]+/', $poll_device['sysDescr'], $hardwarematches);
$hardware = $hardwarematches[0];