In an attempt to gain VNC access to a remote box I threw this silly command at its firewalld over ssh i.e.
$ firewall-cmd --enable 5903:tcp
Now I cannot ssh, ping or curl the server. Whoops.
Can anybody explain what has caused this to happen? I mean surely --enable on its own would enable the firewall and its default rules (i.e. ssh access being one of them) right? As you can probably tell I didn't read the manual- fundamental human error. Also note I ran the command as a normal user, not as root or via sudo. Thanks all :(