Ubiquiti - Unifi Cloud Gateway Persistent ZeroTier Install - Possible Solution

[YodaMcFries]

Hi All!

We've created a semi-solution for Persistent ZeroTier installs on the new Unifi Cloud Gateway (UCG) Series
For context:
The issue we are having is that after a firmware upgrade the UCG does not reinstall any packages in the /config/data/firstboot/install-packages/ directory like the UDM series does, however, the UCG keeps the config file for the ZeroTier installation, meaning a quick reinstall of the package and the UCG reconnects to the network and all is well.

To resolve this we have implemented the following:
Follow this guide on the ZeroTier Website under the ''ARM64" tab
https://docs.zerotier.com/ubiquiti/

Once ZeroTier is installed and working, the following can be done.

A script is to be created that installs the ZeroTier application if it is not already installed:
Create the following script file:

vi /config/data/firstboot/install-packages/install.sh

Once in the text editor paste the following:

#!/bin/sh
 
# Install ZeroTier if it's not already installed
if ! command -v zerotier-cli >/dev/null 2>&1; then
    dpkg -i /config/data/firstboot/install-packages/zerotier-one.deb
fi

Once this is pasted save and quite the file.
After that, run the following command to make the script executable

chmod +x /config/data/firstboot/install-packages/install.sh

For the script to be run after an upgrade you will need to create a persistent service that runs on boot.

To do this you will need to paste the following command:

sudo tee /etc/systemd/system/zerotier-reinstall.service > /dev/null << 'EOF'
[Unit]
Description=Install ZeroTier if not present
After=network.target
[Service]
Type=oneshot
ExecStart=/config/data/firstboot/install-packages/install.sh
RemainAfterExit=true
[Install]
WantedBy=multi-user.target
EOF

Once this has been done, run the following command to enable this service to run on boot.

systemctl enable zerotier-reinstall.service

Your system should now have a persistent ZeroTier installation, Congrats!