I’m trying to set up a somewhat weird network configuration, three interfaces on a pi, an adhoc AP, a wireless lan, and a USB modem.

I want clients of the USB device to talk to clients of the AP, I want clients of the AP to talk to other clients and a single host on the wireless network.

Sorta simple right? Just a couple firewall rules? Well NetworkManager is a land of logical defaults that do not like to be adjusted. I had it working where the AP clients could not reach out to the internet, but could reach the USB clients. NetworkManager automagic’d a NFTables ruleset that doesn’t appreciate being changed.

Okay so I’ll tell NM to not use a firewall backed in the conf, firewall-backend=none, easy.

But once NM is restarted, the networking is behaving like the firewall is still active, despite NFtables and iptables reporting no rulesets, as NM has taken its ball and gone home.

I can’t even figure out a baseline of “what the fuck is going on” because the level of opaque NM automagic happening behind the scenes. I just poke at it and hope something happens. Half the NetworkManager behavior is hidden in dev blog posts that you need to sift through, the official documentation just basically gives the bare minimum info for a feature.

      • lemmyvore@feddit.nlEnglish
        3·
        27 days ago

        🤦 Then you probably shouldn’t uninstall it. When you enter a discussion about an advanced use case people are going to assume you want to manage /etc/resolv.conf and the network interfaces by hand.

          • 8Bitz0@discuss.tchncs.de
            2·
            26 days ago

            You’re telling me you don’t want to update a configuration that updates a configuration that updates a configuration?

            Just wait until you use Ubuntu cloud-init which updates netplan which then updates NetworkManager.

            • delirious_owl@discuss.online
              1·
              26 days ago

              But once NM is gone, I don’t even know how to update the thing that updates the thing that updates the thing.

              My point is that NM is pretty baked-in, and I don’t know how to remove it without breaking things

              • qpsLCV5
                1·
                26 days ago

                use arch btw ;)

                mostly kidding, but shit like this is exactly why i love arch so much. set up the entire system from ground up - no bullshit on it, and you know how (almost) every part works and what it does.

        • theshatterstone54@feddit.uk
          1·
          26 days ago

          I’ve been wondering about how feasible an all-systemd system would be. Like, take Arch and do a manual install but replace everything possible with systemd. Resolved, networkd, (whatever the fstab alternative is called), systemd-boot (of course) etc. And just have everything replaced by systemd as much as possible. It’s an interesting idea and ClearLinux essentially did just that so I might check it out for inspiration.

          • allywilson
            1·
            26 days ago

            I think Poettering did a blog post just before he left RedHat (or maybe it was just after) where he described his ‘perfect’ OS - it was pretty detailed, I imagine it was indeed what we’d call systemd+Linux

            Edit: Found it

            • theshatterstone54@feddit.uk
              1·
              26 days ago

              Holy crap, that dude is just next level. He’s talking about getting absolutely everything encrypted, and here I am, not even having my root partition encrypted.