Comment 5 for bug 1902945

Juju 2.9 has become more strict with how it deals with charm channels. And also support for snap like semantics is being introduced, to allow track and risk instead of juju channel.

The issue here is that the kubeflow bundle specifies a default channel of "stable". Well, there is no channel and so a default of stable is assumed. And there are no charm specific channels. So Juju will look for stable versions. But most of the kubeflow charms are only on edge. The ones that do have stable versions (eg katib) do deploy properly.

So the kubeflow bundle needs to specify a default risk of edge, or it needs to add edge to the charms which need it.

Having said that, there does appear to be a juju bug where a charm specific channel does not override the bundle value. So that needs fixing. But the kubeflow bundle also needs updating.

It worked with 2.8 because 2.8 was broken in how it searched for charms - it accepted any old charm risk if none were otherwise specified, ie it does not default to stable. But snaps do and we are adopting the snap behaviour for 2.9.