RFE: unable to deploy machine charm with a base other than ubuntu when using metadata v2

[Jon Seager]

It seems that machine charms using metadata v2 can only deploy where some variant of Ubuntu is specified as a base.

There is a simple charm for demonstration here: https://gist.github.com/jnsgruk/322c0058e361255fd7a529dc8fd6d196

If you follow the README and deploy the charm as is, it will deploy a LXC container running on Ubuntu 20.04.

If you edit the generated "machine-charm.charm` package, and update `manifest.yaml` to specify CentOS, or similar:

```
bases:
  - architectures:
      - amd64
    channel: "7"
    name: centos
charmcraft-started-at: "2021-05-05T11:46:37.835347Z"
charmcraft-version: 1.0.0
```

The charm will then fail to deploy with the error:

```
ERROR series not specified and charm does not define any
```

[Simon Richardson (simonrichardson)]

The current workaround for this is that `channel: "centos7"`.

[Pen Gale (pengale)]

Moved to 2.9.8, as there is extensive work and coordination needed in order to fix this. (Work is ongoing.)

[Heather Lanigan (hmlanigan)]

Today, charmcraft only supports ubuntu in a base. Adding new operating systems will be a roadmap item in the (near) future. This work will have a juju component as well to be done.

[Heitor (heitorpbittencourt)]

We are hitting something similar, see https://bugs.launchpad.net/juju/+bug/1949622

[Jon Seager (jnsgruk)]

I'm going to close this, it's no longer relevant given that we will discontinue RHEL/CentOS support in Juju for Juju 4.0