Disable WAN Interface on CARP Backup

10-wancarp

#last updated for opnsense 24.7.11_2
#!/usr/local/bin/php
<?php

require_once("config.inc");
require_once("interfaces.inc");
require_once("util.inc");
require_once("system.inc");

$subsystem = !empty($argv[1]) ? $argv[1] : '';
$type = !empty($argv[2]) ? $argv[2] : '';

if (!in_array($type, ['MASTER', 'BACKUP', 'INIT'])) {
    log_msg("Carp '$type' event unknown from source '{$subsystem}'");
    exit(1);
}

if (!strstr($subsystem, '@')) {
    log_error("Carp '$type' event triggered from wrong source '{$subsystem}'");
    exit(1);
}

$ifkey = 'wan';
$real_if = get_real_interface($ifkey);

# since all my CARP ips fail over together, I just wanted it to only run when it matched the CARP status change for my LAN interface. You can find it in your debug log searching for 'carp' and/or totally comment out the IF statement.
	if ($subsystem === "200@vtnet1") {
if ($type === "MASTER") {
    log_error("enable interface '$ifkey' due CARP event '$type' on '$subsystem'");
    $config['interfaces'][$ifkey]['enable'] = '1';
    write_config("enable interface '$ifkey' due CARP event '$type'", false);
    interface_configure(false, $ifkey, false, false);
    sleep(2);
    shell_exec("/sbin/ifconfig {$real_if} up");
    log_msg("Issuing dhclient command on '$real_if' to request a DHCP lease");
    sleep(1);
    shell_exec("dhclient {$real_if}");

} else {
    log_error("disable interface '$ifkey' due CARP event '$type' on '$subsystem'");
    unset($config['interfaces'][$ifkey]['enable']);
    write_config("disable interface '$ifkey' due CARP event '$type'", false);
    interface_configure(false, $ifkey, false, false);
    shell_exec("/sbin/ifconfig {$real_if} down");
}
	} #if subsystem