works once, not after server reboot

robotro77

I am using road warrior openvpn install script from https://github.com/Nyr/openvpn-install/blob/master/openvpn-install.sh

This is rather weird, but the script works fine, on fully updated (3/2021) remote debian 9.2 server.
I get my username.opvn file back, and I can connect. Everything works. When I reboot remote server, it no longer works. I was able to reproduce this behavior, by running option 3, removing openvpn (I have my suspicion that some /etc config files remained), restarting, running the script again, running openvpn and connecting, but not after restart...why? why?

if I check running processes using ps -elf | grep openvpn there is nothing except my ps

if I check status, I got this:

me@debian:~$ sudo systemctl status openvpn@*
● openvpn@server.service - OpenVPN connection to server
   Loaded: loaded (/lib/systemd/system/openvpn@.service; disabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Mon 2021-03-08 23:10:07 EST; 14min ago
     Docs: man:openvpn(8)
           https://community.openvpn.net/openvpn/wiki/Openvpn23ManPage
           https://community.openvpn.net/openvpn/wiki/HOWTO
  Process: 280 ExecStart=/usr/sbin/openvpn --daemon ovpn-server --status /run/openvpn/server.status 10 --cd /etc/openvpn --config /etc/openvpn/server.conf --writepid /r
 Main PID: 350 (code=exited, status=1/FAILURE)

Mar 08 23:10:07 debian ovpn-server[350]: /sbin/ip addr add dev tun0 10.8.0.1/24 broadcast 10.8.0.255
Mar 08 23:10:07 debian ovpn-server[350]: Could not determine IPv4/IPv6 protocol. Using AF_INET
Mar 08 23:10:07 debian ovpn-server[350]: Socket Buffers: R=[212992->212992] S=[212992->212992]
Mar 08 23:10:07 debian ovpn-server[350]: TCP/UDP: Socket bind failed on local address [AF_INET]xxx.yyy.zzz.www:1194: Cannot assign requested address
Mar 08 23:10:07 debian ovpn-server[350]: Exiting due to fatal error
Mar 08 23:10:07 debian ovpn-server[350]: Closing TUN/TAP interface
Mar 08 23:10:07 debian ovpn-server[350]: /sbin/ip addr del dev tun0 10.8.0.1/24
Mar 08 23:10:07 debian systemd[1]: openvpn@server.service: Main process exited, code=exited, status=1/FAILURE
Mar 08 23:10:07 debian systemd[1]: openvpn@server.service: Unit entered failed state.
Mar 08 23:10:07 debian systemd[1]: openvpn@server.service: Failed with result 'exit-code'.

this line right here appears to be the problem, maybe?

TCP/UDP: Socket bind failed on local address [AF_INET]xxx.yyy.zzz.www:1194: Cannot assign requested address

but why? why it works once but not after reboot?

TinCanTech

The error message usually means that openvpn is running already ..

robotro77

I checked that it is not running, using ps command

TinCanTech

Then you have something else using the port.

robotro77

there seems to be some confusion in my head and on my vm, because
sudo systemctl status openvpn@*
addreseses somethinhg entirely different than
sudo systemctl status openvpn-server@*

TinCanTech

They are two different systemd unit files for openvpn.

openvpn-server@* is the official openvpn unit file.
openvpn@* is your distro unit file, which has not caught up with openvpn, yet.

But you need to learn about systemd now.

robotro77

TinCanTech wrote Then you have something else using the port.

checked that with netstat, nothing else (except sshd) is running

TinCanTech

Then you did something else wrong.

Please start here:
https://forums.openvpn.net/viewtopic.php?f=30&t=22603#p68963

Or ask Nyr what is wrong with his script.