Enable ipv6 network by default

[maflcko]

Feature request description

Currently ipv6 is not supported by default out of the box:

# dnf install podman -y  &&  podman run -it --rm ubuntu:22.04 apt-get update 
Last metadata expiration check: 0:39:00 ago on Sun 27 Aug 2023 09:53:11 AM UTC.
Package podman-5:4.6.1-1.fc38.aarch64 is already installed.
Dependencies resolved.
Nothing to do.
Complete!
0% [Connecting to ports.ubuntu.com]
...

It is required to specify --network. For example host (insecure), or one created by podman network create --ipv6 network_name.

Suggest potential solution

Set --ipv6 by default out of the box on the default network (podman network inspect podman | grep ipv6_enabled)

Have you considered any alternatives?

no

Additional context

No response

[github-actions]

A friendly reminder that this issue had no activity for 30 days.

[su-ex]

Meep, still relevant!

[rhatdan]

@Luap99 Is this something we can do for podman 5?

[Luap99]

Maybe? Problem is our ipv6 support is still in a somewhat akward state. We would need to use ipv6 NAT which is a bit controversial I guess.

cc @mheon

[mheon]

Our v6 support does have a number of issues - for example, we need to get port forwarding off localhost working. No easy way to do that now (though it'd be interesting to wire that into conmon-rs when we migrate over there). IMO, enabling by default is a low priority for Podman 5 (mainly because we have so much else we need to do)

[rhatdan]

I am wondering if the importance of this might change from Red Hat's point of view.

[WhyNotHugo]

This breaks trying to use podman as a drop-in replacement for docker. Even for the most basic commands like docker run --rm --publish 8001:8001 mycontainer.