For multiple locations we decided to use this model because if very cheap and powerful.
First we had to decide to use between Zerotier and Wireguard but because of the time that zerotier is very easy to configure and because branches only have to access a webserver page we choose Zerotier.

First tutorial on the internet showed us that is working with no problems on verson 2.X from Ubiquiti but we wanted go further just to be easier later on. In the tutorial is explained how to have this tunnel as a normal interface. One of the benefit i have in mind is having firewall rules, access lists later on. As we had the simple model with 5 ports (starts from eth0) we choose to have eth5 as zerotier and here the problem started.

root@ubnt:/config/scripts/zerotier-one# vi  /var/lib/zerotier-one/devicemap
root@ubnt:/config/scripts/zerotier-one# /etc/init.d/zerotier-one restart
 [ ok ] Restarting zerotier-one (via systemctl): zerotier-one.service.

Because i did this remotely, immediately after i restarted zerotier services, router bricked in kernel panic mode. That’s it. A reboot won’t solve the problem, a hardware restart as well.
So we had to use a UAV serial port from a Raspberry Pi 4 and start recovery. I’m not going into details as is explained here and into ubiquiti website as well.

How to avoid this?

Well, looks like the problem is related to this model, EdgeRouter X. This model have also 6 ports, including eth5 (that is used for SFP) and because somewhere in the configuration this port exist, this might be our problem. After recover, i reconfigure this but using eth6 and it’s working with no problems.
Few pictures from the recovery: