Missing Pulp 3 workers on upgrade to Katello 4.0

I believe this may be the same thing:

As for stopping services: I’m always hesitant with that. In complex multi-machine deployments it’s harder to orchestrate.

Another thing I’d like to ask is whether it’s needed for patch releases as well or if we can limit it to minor releases.

Does this mean we need to stop all services (all workers, orchestrator, content and API) or only the workers or orchestrator?

Thinking out loud: can we set a cache key somewhere that makes Pulp workers stop accepting jobs? Perhaps the Django DB migrations could set (and unset) this. The question is then still open of what to do with workers that are still processing jobs.