It is possible that when installing the zerotier client on Debian 11.4 an error occurs
curl: (6) Could not resolve host
apparently it is a PHP 7.4 installation error.
Therefore it is recommended to reinstall it with the following command:
sudo apt -y reinstall php7.4
Later you can use the instructions indicated at: Download – ZeroTier
Linux section and run the command line:
curl -s https://install.zerotier.com | sudo bash
If the result is:
Success! You are ZeroTier address [ IDxxxxxxxx ].
All that remains is to join with the instruction:
zerotier-cli join IDxxxxxxx
and If the result is:
200 join OK
It means that everything went well
Enjoy - Disfrutalo!