IPv6 Support for Containers

Community
1

At present, IPv4 network interfaces are supported out of the box and work well with container networking. We would like to work on IPv6 support for the HTCondorCE container. You can use this topic to track progress or to let us know how urgently this is required. If you would like to join the effort or help test the functionality, just reply to this topic.

From a quick research, it seems we need to modify the docker daemon configuration as follows:

{

“ipv6”: true,

“fixed-cidr-v6”: “2001:db8:1::/64”

}

We need to decide/test:

  1. If the CIDR should be automatically detected by the framework, or if it should be specified in the site level configuration file.
  2. Test if Docker Swarm managers can be dual stack host network interfaces as their advertise-addr

Here are some relevant sources:

  1. https://docs.docker.com/config/daemon/ipv6/
  2. https://collabnix.com/enabling-ipv6-functionality-for-docker-and-docker-compose/

@litmaath @esilvaju thoughts?

2

Hi all, I think we should let the admin configure any networking explicitly for now, as I do not think we can just assume that IPv4 and/or IPv6 are “OK” simply because such addresses were set up in the local DNS. Of course, the DNS should be realistic, but often enough I have seen that services up- or downstream had different ideas about which network stacks actually are supported for a particular host… :frowning: