TrueNAS Scale

You can directly bring up a Wireguard interface in TrueNAS Scale, and use that to remotely manage it.

Wireguard isn’t exposed in the GUI, so use the command line to create a config file and enable the service. To make it persistent between upgrades, add a cronjob to restore the config.

Configuration

Add a basic peer as when setting up a Central Server and save the file on the client as /etc/wireguard/wg1.conf. It’s rumored that wg0 is reserved for the TrueNAS cloud service. Once the config is in place, use wg-quick up wg1 command to test and enable as below.

nano /etc/wireguard/wg1.conf

systemctl enable --now wg-quick@wg1

If you use a domain name in this conf for the other side, this service will fail at boot because DNS isn’t up and it’s not easy to get it to wait. So add a pre-start to the service file to specifically test name resolution.

vi /lib/systemd/system/[email protected]

[Service] 
...
...
ExecStartPre=/bin/bash -c 'until host google.com; do sleep 1; done'

Note: Don’t include a DNS server in your wireguard settings or everything on the NAS will attempt to use your remote DNS and fail if the link goes down.

Accessing Apps

When deploying an app, click the enable “Host Network” or “Configure Host Network” box in the apps config and you should be able to access via the VPN address. On Cobia (23.10) at least. If that fails, you can add a command like this to a post-start in the wireguard config file.

iptables -t nat -A PREROUTING --dst 192.168.100.2 -p tcp --dport 20910 -j DNAT --to-destination ACTUAL.LAN.IP:20910

Detecting IP Changes

The other side of your connection may dynamic address and wireguard wont know about it. A simple solution is a cron job that pings the other side periodically, and if it fails, restarts the interface. This will lookup the domain name again and hopefully find the new address.

touch /etc/cron.hourly/wg_test
chmod +x /etc/cron.hourly/wg_test
vi /etc/cron.hourly/wg_test

#!/bin/sh
ping -c1 -W5 192.168.100.1 || ( wg-quick down wg1 ; wg-quick up wg1 )

Troubleshooting

Cronjob Fails

cronjob kills interface when it can’t ping

or

/usr/local/bin/wg-quick: line 32: resolvconf: command not found

Calling wg-quick via cron causes a resolvconf issue, even though it works at the command line. One solution is to remove any DNS config from your wg conf file so it doesn’t try to register the remote DNS server.

Nov 08 08:23:59 truenas wg-quick[2668]: Name or service not known: `some.server.org:port' Nov 08 08:23:59 truenas wg-quick[2668]: Configuration parsing error … Nov 08 08:23:59 truenas systemd[1]: Failed to start WireGuard via wg-quick(8) for wg1.

The DNS service isn’t available (yet), despite Requires=network-online.target nss-lookup.target already in the service unit file. One way to solve this is a pre-exec in the Service section of the unit file¹. This is hacky, but none of the normal directives work.

The cron job above will bring the service up eventually, but it’s nice to have it at boot.

Upgrade Kills Connection

An upgrade comes with a new OS image and that replaces anything you’ve added, such as wireguard config and cronjobs. The only way to persist your Wireguard connection it to put a script on the pool and add a cronjob via the official interface².

Add this script and change for your pool location. This is set to run every 5 min, as you probably don’t want to wait after an upgrade very long to see if it’s working. You can also use this to detect IP changes over the cron.hourly above.

# Create the location and prepare the files
mkdir /mnt/pool02/bin/
cp /etc/wireguard/wg1.conf /mnt/pool02/bin/
touch /mnt/pool02/bin/wg_test
chmod +x /mnt/pool02/bin/wg_test

# Edit the script 
vi /mnt/pool02/bin/wg_test

#!/bin/sh
ping -c1 -W5 192.168.100.1 || ( cp /mnt/pool02/bin/wg1.conf /etc/wireguard/ ; wg-quick down wg1 ; wg-quick up wg1 )


# Invoke the TrueNAS CLI and add the job
cli
task cron_job create command="/mnt/pool02/bin/wg_test" enabled=true description="test" user=root schedule={"minute": "*/5", "hour": "*", "dom": "*", "month": "*", "dow": "*"}

Notes

https://www.truenas.com/docs/core/coretutorials/network/wireguard/ https://www.truenas.com/community/threads/no-internet-connection-with-wireguard-on-truenas-scale-21-06-beta-1.94843/#post-693601