I'm trying to figure out whether the host network I am on is injecting TCP Resets into my VPN connection.
I have a personal OpenVPN server, and recently my attempts to connect over TCP port 1194 have been strangely interrupted by TCP reset messages, causing the OpenVPN client to enter a reboot-loop. I suspect the local network infrastructure does not like this, and is trying to block it. After changing the port to 1195 this issue disappears entirely, indicating this isn't just some bug in the openVPN client or server.
So my question is this: Is this mysterious injection of TCP resets a common trick to block unwanted connections? It seems a little strange -- why don't they just block the port or send other TCP control messages to terminate the connection? Last week, I was connecting over TCP to port 1194 without issue. The strange TCP resets just appeared this week.
Thanks in advance!