Webmin has come a long way in the last year or two. I still (and always will) prefer the command line, but many customers are certainly much more comfortable using a web-interface to configure their server. I have to reset a password every once in a while and have to look up the steps every time. It seems I can never find them quickly, so I’ll put them here so I can find them easily next time.
Blocked IP addresses are stored a text file named /var/webmin/blocked. IP Address should be cleared out after some period of time, but you can hasten the process by clearing it manually:
cp /dev/null /var/webmin/blocked
Webmin passwords are stored in /etc/webmin/miniserv.users. A script for changing a user password is provided with webmin. Just run it like this:
/usr/libexec/webmin/changepass.pl /etc/webmin root