Server lost connectivity after setting IP from DHCP to manual

[ramones79]

SYSTEM INFORMATION
OS type and version	Ubuntu 20
Virtualmin version	Latest

Hello,
I have 2 issues:

1. I’ve installed OpenVPN along existing Virtualmin server.
   All worked well, until server reboot.

OpenVPN client was not able to connect anymore.
I’ve allowed the UDP port for OpenVPN and the client then was able to connect.
However, after connecting to the OpenVPN server, there was no network connectivity, making the VPN inoperable in practice.

I supposed this has to do with how the network on the VPS is configured, since I was receiving IPv6, instead of IPv4 on the OpenVPN client.
I’ve noticed, that the IP is not hardly set, instead Virtualmin was set to get it over DHCP.

2. I’ve manually input the IP and used net mask 255.255.255.0

After that all connectivity to the server whatsoever was lost.

Any suggestions?
ps. I have backup and last resort solution will be to reinstall the server completely and restore from backup.
Anyway, if you have a suggestion on how OpenVPN should be allowed in Virtualmin’s firewall, so it works well, I’ll appreciate any help?

Thanks.

[ramones79]

I’ve fixed the server and restored connectivity.
However, it turns out that Virtualmin is incompatible with either OpenVPN or WireGuard.
They both install fine and work - until you have to reboot the server.
Both VPN solutions cannot survive Virtualmin reboot - the symptoms are the same - client connects, but no traffic at all.

So, Virtualmin/Webmin is somehow overwriting their settings (network, firewall).

If anybody has a suggestion on how to make Virtualmin work along with VPN and survive reboots?

Thank you.

[ramones79]

Found simple solution, that works:

1. Add the VPN port in FirewallD and apply
2. Use

sudo iptables-save

After that WireGuard can survive a Virtualmin reboot.
I’ve not tested it yet with OpenVPN, but I think it should work too.

ps. I’ve also activated “Act like a router” option in Network config, not sure if it’s actually necessary.