cross-posted from: https://programming.dev/post/39212874
I recently migrated my services from rootful
docker
to rootlesspodman quadlets
. It went smoothly, since nothing I use actually needs to be rootful. Well, except forcaddy
. It needs to be able to attach to privileged ports 80 and 443.My current way to bypass it is using
HAProxy
running as root and forwarding connections using proxy protocol. (Tried to usefirewalld
but that makes the client IP opaque tocaddy
.) But that adds an extra layer, which means extra latency. It’s perfectly usable, but I’d like to get rid of it, if possible.I’m willing to run
caddy
in rootfulpodman
if needed. But from what I understand, that means I can’t have it in the same rootless network as my other containers. I really don’t wanna open most of my containers’ ports, so that’s not an option.So, I’m asking whether any of these three things are possible.
- Use
firewalld
to forward ports tocaddy
without obscuring the client’s IP.- Make rootful
caddy
share a network with other rootless containers.- Assign privileged ports to caddy somehow, in rootless mode. (I know there’s a way to make all these ports unprivileged, but is it possible to only assign these 2 ports as unprivileged?)
Or maybe there’s a fourth way that I’m missing. I feel like this is a common enough setup, that there must be a way to do it. Any pointers are appreciated, thanks.
TBH I haven’t played with passing caddy’s podman network to other containers, mine is a simple reverse proxy to other standalone containers but not directly connected via
podman run --network
(or quadlet network). In my scenario I can at least confirm thatnet.ipv4.ip_unprivileged_port_start
doesn’t need to be modified, the only annoyance is that I cannot use a systemd user service, even though the end process doesn’t run as root.EDIT: Actually looking at the examples a bit more closely I think the primary difference with my setup is that the systemd socket is started with
systemd --user
which thus requires the sysctl change, whereas I’m not using a systemd user service, relying instead onUser=some-non-root-user
to use rootless podman, but requiring root privileges to manage the systemd service.