Interface name needed in IPv6 address from multipass VM (but not from host or non multipass VM)

[saviq]

@tfa61

But there is only one interface! This is a Ubuntu limitation, because we don’t have to provide it from the Windows 10 VM in the same segment.

If anything, a Linux one. Not specific to Ubuntu or Multipass.

@tfa61

Is this related to the IP addresses not appearing in Ubuntu VMs properties in Hyper-V?

No, that’s because the Windows VM has guest additions that report the IPs to Hyper-V.

@tfa61

How can I do that? I don’t see any parameters for that, so I guess this could be done with a cloud-init file. What would its syntax for that?

In Ubuntu, you’d use netplan inside the instance.

@tfa61

My need is to be able to launch a bunch of multipass VMs than can communicate through IPv6 between them. The aim is to simply verify connectivity of a program I want to test. This program doesn’t have any means to pass the interface name to use (contrary to ping program).

There will be a dozen of VMs, so a unique cloud-init file shared by all of them would be a plus.

The Hyper-V DefaultSwitch, that provides default networking to Hyper-V VMs, does not seem to support IPv6 DHCP, which is why link-local addresses are used.

The best I can offer you is to use the new --network feature of Multipass (available in 1.6.0 RC), ensuring that whatever Virtual Switch you choose sets up IPv6 properly over DHCP, or that you add static netplan configuration for them, having used --network "id=…,mode=manual".