Re: [atomic-devel] firewalld in atomic host

On Fri, Apr 21, 2017 at 10:16 AM, Dusty Mabe <dusty dustymabe com> wrote:

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I'd like to discuss firewalld on atomic host. Recently I was trying to
figure out the best way to explain to other users how to set firewall rules
on atomic host.

Usually I would say add your rules and then iptables-save, but on Atomic
Host docker has added it's firewall rules in there dynamically so if you iptables-save
you'll get a bunch of stuff that you don't want in your static configuration.

There are ways around this; manually create your config file, or use iptables-save
and then rip the docker stuff out. Either way it's a bit of a pain. I think
firewalld would make this easier on the user. Not sure of the pro/con ratio though.

While I can see firewalld improving the situation wrt documenting how to add/persist firewall changes for Atomic Host (especially when using moby/docker), I think there is a bigger concern with firewalld being absent. If a user is running multiple applications that modify the host firewall (docker, Kubernetes, OpenShift, etc), firewalld provides a way to make firewall modifications in a consistent and repeatable manner, where iptables does not. There is the --wait flag for iptables, however any applications/users that are interacting with iptables will need to ensure they use it consistently.

Jason DeTiberus