Question: network with predictible hostnames

[vsoch]

I'm bringing up multiple VMs, and adding them to the same user network:

limactl start --network=lima:user-v2 --name=flux-0 ./flux-usernetes.yaml
limactl start --network=lima:user-v2 --name=flux-1 ./flux-usernetes.yaml

Looking at the instructions here https://lima-vm.io/docs/config/network/#lima-user-v2-network that seems to be the last option. What I'm able to do is get the actual ip address from ip a and then update /etc/hosts of each, adding the hostnames:

192.168.104.6  lima-flux-0
192.168.104.7  lima-flux-1

And then my application can query for lima-flux-0 or lima-flux-1 and it's associated with an address. I'm wondering if there is a way to automate this, so I could ping lima-flux-0 and get that address without needing to modify /etc/hosts? Note that the hostname command returns the correct name in the VM, but I can't use that to ping another one (without the addition. Thank you!

[AkihiroSuda]

We should enhance the built-in DNS to support looking up hostnames.

A workaround would be to use mDNS, but I couldn't get it to work.

[balajiv113]

then update /etc/hosts of each

For user-v2 it should already work. If you call lima-flux-0.internal from lima-flux-1 instance.

Just that you need to user .internal suffix for it to work. I remember this was documented somewhere i will check and add if this is not captured

[AkihiroSuda]

sshuttle --dns --auto-nets --ssh-cmd "ssh -F $HOME/.lima/vm0/ssh.config" --remote lima-vm0 seemed to work, but also seems to break looking up Internet domains (nslookup google.com).
This may work stably with some additional options.

[vsoch]

It worked great for me! I'm still working on my changes but I'll push (and link) soon. I'm on ubuntu 22.04 and i used the user-v2 network, and I could ping lima-flux-0 from lima-flux-1 and vice versa without adding anything to /etc/hosts

[vsoch]

okay here is the current configuration(s) etc. for what I'm working on (and adding .internal works to bootstrap my VM cluster) https://github.com/converged-computing/flux-lima/tree/main/usernetes#sanity-checks. This is a WIP so it will likely be changing vs. not!

[AkihiroSuda]

Opened a PR for docs:

• docs/config/network: mention lima-<NAME>.internal #2156

[fwilhe2]

Wasn't aware of the user-v2 networking mode, this seems super useful to me. Thanks everyone for building/documenting it! 🚀