librenms-librenms/includes/discovery/ucd-diskio.inc.php

<?php

$diskio_array = snmpwalk_cache_oid($device, 'diskIOEntry', [], 'UCD-DISKIO-MIB');
$valid_diskio = [];
if (is_array($diskio_array)) {
    foreach ($diskio_array as $index => $entry) {
        if (($entry['diskIONRead'] > '0' || $entry['diskIONWritten'] > '0') && is_disk_valid($entry, $device) === true) {
            d_echo("$index " . $entry['diskIODevice'] . "\n");

            if (dbFetchCell('SELECT COUNT(*) FROM `ucd_diskio` WHERE `device_id` = ? AND `diskio_index` = ? and `diskio_descr` = ?', [$device['device_id'], $index, $entry['diskIODevice']]) == '0') {
                $inserted = dbInsert(['device_id' => $device['device_id'], 'diskio_index' => $index, 'diskio_descr' => $entry['diskIODevice']], 'ucd_diskio');
                echo '+';
                d_echo($sql . " - $inserted inserted ");
            } else {
                echo '.';
                // FIXME Need update code here!
            }

            $valid_diskio[$index] = $entry['diskIODevice'];
        } //end if
    } //end foreach
} //end if

// Remove diskio entries which weren't redetected here
$sql = "SELECT * FROM `ucd_diskio` where `device_id`  = '" . $device['device_id'] . "'";

d_echo($valid_diskio);

foreach (dbFetchRows($sql) as $test) {
    d_echo($test['diskio_index'] . ' -> ' . $test['diskio_descr'] . "\n");

    if ($valid_diskio[$test['diskio_index']] !== $test['diskio_descr']) {
        echo '-';
        dbDelete('ucd_diskio', '`diskio_id` = ?', [$test['diskio_id']]);
    }
}

unset($valid_diskio);
echo "\n";