librenms-librenms/includes/discovery/sensors/state/serveriron.inc.php

<?php

echo 'ServerIron States';

// All those states are : (Value: 1 Other, 2 Normal, 3 failure) (Power Supply and Fans)

// Power Supplies
for ($i=1; $i != 3; $i++) {
    $power_oid    = '.1.3.6.1.4.1.1991.1.1.1.2.1.1.3.'.$i;
    $power_status = snmp_get($device, $power_oid, '-Oqv');
    if (!empty($power_status)) {
        discover_sensor($valid['sensor'], 'state', $device, $power_oid, 'powerstatus'.$i, 'snmp', 'Power Supply '.$i.' Status', 1, 1, '1', null, null, '3', $power_status);
    }
}

// Fan status
for ($i=1; $i != 7; $i++) {
    $fan_oid    = '.1.3.6.1.4.1.1991.1.1.1.3.1.1.3.'.$i;
    $fan_status = snmp_get($device, $fan_oid, '-Oqv');
    if (!empty($fan_status)) {
        discover_sensor($valid['sensor'], 'state', $device, $fan_oid, 'fanstatus'.$i, 'snmp', 'Fan '.$i.' Status', 1, 1, '1', null, null, '3', $fan_status);
    }
}