Notice of Debian 11 issue (firewalld) - and a work around

[KNERD]

Today, I installed Webmin to help with making it simpler to manage the server, and other goodies it has.

With ASTPP, they are using the default FirewallD.

Since Webmin needs port 10000 TCP open, I entered the following commands.

firewall-cmd --permanent --zone=public --add-port=10000/tcp
firewall-cmd --reload

Upon executing the second command, I got the following error:

Error: COMMAND_FAILED: ‘/sbin/ip6tables-restore -w -n’ failed: ip6tables-restore v1.8.2 (nf_tables):
line 4: RULE_REPLACE failed (No such file or directory): rule in chain INPUT
line 4: RULE_REPLACE failed (No such file or directory): rule in chain OUTPUT

I also noticed all the open ports in iptables had been wiped out. So I had to go and re-enter then, including port 22 for SSH.

The workaround is to change the following in:

/etc/firewalld/firewalld.conf

Change InvividualCalls=no to InvividualCalls=yes then reboot before trying to make changes like I did.

PS: I always do “systemctl stop webmin” when not using because there may be an exploit.

[sman123]

@sman123

I have webmin set to only listen on localhost. Then I create an SSH tunnel mapping localhost:10000 to my PC using PuTTy. More complicated than just shutting down the service when not in use but it’s very secure and no danger of forgetting to shut down the service.

I have webmin set to only listen on localhost. Then I create an SSH tunnel mapping localhost:10000 to my PC using PuTTy. More complicated than just shutting down the service but it’s very secure, and no danger if you forget to shut down the service.