I was setting up a server with some firewall settings and seem to have locked myself out. This is the first time I have used "webmin Linux Firewall" to do the configuration settings.
What I did was simple. I accepted the option at the beginning to "allow all traffic". Then, I wanted to block one particular IP address from access, so for Incoming Packets I clicked on Add Rule, Action to Take = Drop, Source address or network = the IP address, clicked on the create button, applied the configuration, and then everything went dead. Everywhere. All IP addresses from anywhere I could try. Unfortunately Active at Boot was also set, so rebooting won't get me to "start over".
I am hoping that someone with knowledge of what Webmin does here will know what exactly the settings would have been saved as, and possibly know what might work to get me back in again.
Fortunately this is a utility server, so no public sites have gone offline. But it would take a while to rebuild everything that's on here.
This is on an Amazon instance, for what it's worth.