NethServer Version: 7.4 Module:
This afternoon I was confronted with a very odd situation. I rebooted my VPS server and after reboot the server was responding a few seconds, after 10 pings, the server doesn’t respond anymore: Not on pings, not trhough ssh nor webinterface…
Fortunately I can set up a VNC session (the VPS is running on proxmox) and I can access the terminal through that.
What should I do now to troubleshoot this?
I mainly use the server as mailserver (SOGo) with Samba4 AD account provider.
networking: eth0 is having an external IP addres (directly connected to internet)
eth1 is created through a dummy interface and is bridged so nsdc is installed using an IP on the green subnet.
I don’t know if it is related, but I did install nethserver-openvpn this afternoon. I removed that again through the terminal in the VNC session.
From the VNC terminal I can reach any IP address and webaddress through ping and nslookup, so networking looks like fine.
As soon as I stop shorewall, the webinterface is loading fine again. When I start shorewall, everything is blocked again. So it looks like shorewall is the culprit here.
any guidance appreciated…
Looks like I encountered the paower of getting myself locked out by fail2ban… I did a few attempts to connect with openvpn, and that triggered fail2ban to blacklist my IP.
Good to know fail2ban works as it should…
The IP is still listed in DB as banned…
In the meantime my ISP decided to change my IP address (yeah in .be there is still no static IP’s) so the problem seems to have solved itself…