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On CentOS 7 have I been trying out different firewalld rules and iptables commands, and now want to do it all over, but only using firewalld.

Question

How can I reset all rules to the default that CentOS 7's firewalld ships with?

Louise Hoffman
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5 Answers5

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Following piece of Code may be helpful for you.

for srv in $(firewall-cmd --list-services);do firewall-cmd --remove-service=$srv; done firewall-cmd --add-service={ssh,dhcpv6-client} firewall-cmd --runtime-to-permanent

Regards,

Ahmer Mansoor

Ahmer Mansoor
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If you trully want to delete everything as John Ashpool say's

rm -rf /etc/firewalld/zones or /usr/etc/firewalld/zones depending on your distro

and 

iptables -X
iptables -F
iptables -Z

plus 

systemctl restart firewalld

and then you have a new set of rules and zones ;)

denn0n
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You may simply delete the files containing the customized zone rules from /etc/firewalld/zones (or /usr/etc/firewalld/zones, depending on the distribution). After that, reload firewalld with firewall-cmd --complete-reload, and it should start using the default settings. When you make changes to the zone rules, files will appear again in that directory.

As for iptables, you may reset all rules with iptables -F. Rebooting works as well, unless you implemented some sort of persistency. Beware that firewalld may be configured to use iptables as its backend, which means it will add or remove iptables rules itself, according to what you specified in its zone rules.

ashpool
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Any default zones that come with distribution, if modified, get copied to /etc/firewalld/zones directory with those modifications.

Which also means that the source of default zone files is not this directory and re-installation doesn't know about the files under this directory (/etc/firewalld/zones) so these files will be untouched by reinstallation. Unless these files are removed, firewalld continues to load your modifications from this directory.

You can backup and delete all those files (safely) from /etc/firewalld/zones and restart firewalld which then comes back to default distribution installed zone configurations.

It is safe in a sense that, the default distribution zone configurations allow SSH by default. However, if you logged into this server via a different port of SSH than 22 or by any other means than SSH, then you need to be careful, removing all those files from /etc/firewalld/zones

sudo cp -pR /etc/firewalld/zones /etc/firewalld/zones.bak
sudo rm -f /etc/firewalld/zones/*
sudo systemctl restart firewalld

In case any other config files are modified, the firewalld itself can be reinstalled, however, the firewalld RPM needs to be downloaded to reinstall it.

Install yum-downloadonly plugin:

(RHEL5)
# yum install yum-downloadonly
(RHEL6, RHEL7)
# yum install yum-plugin-downloadonly

Before using the plugin, check /etc/yum/pluginconf.d/downloadonly.conf to confirm that this plugin is enabled=1

# yum install --downloadonly --downloaddir=/tmp firewalld
# rpm -ivh --force /tmp/firewalld*.rpm

BTW yum reinstall firewalld doesn't replace the modified config files.

VanagaS
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Personally I would just remove all the services and rules from all the zones you have edited. Except for SSH in case you are working on a remote server. That is easy: sudo firewall-cmd --zone=WHATEVER --remove-service=WHATEVER

And after all have been removed, just sudo firewall-cmd --runtime-to-permanent

HOWEVER: If you haven't saved the firewall rules, then just restart with systemctl restart firewalld

I don't think there is any reset function in it.

Bert
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