I’m using the amazing Oban Web+Pro by @sorentwo in a Phoenix app. Previously the jobs were being executed on every node in my cluster, along with the Oban Web dashboard exposed for admins.

But now we’d like to isolate all jobs to only a few dedicated worker nodes, but keep using Oban Web along with the Phoenix app on the other web nodes to monitor job status across all nodes.

I thought it would be as simple as setting the concurrency of my queues to 0 on the web nodes:

config :my_app, Oban
  queues: [
    queue_1: 0,
    queue_2: 0,
    queue_3: 0,
  ]

But this just raises the following error:

** (Mix) Could not start application my_app: MyApp.Application.start(:normal, []) returned an error: shutdown: failed to start child: Oban
    ** (EXIT) an exception was raised:
        ** (ArgumentError) queue :queue_1, local_limit must be greater than 0
            (oban 2.13.6) lib/oban/validation.ex:41: Oban.Validation.validate!/2
            (oban 2.13.6) lib/oban/config.ex:77: Oban.Config.new/1
            (oban 2.13.6) lib/oban.ex:182: Oban.start_link/1
            (stdlib 4.0.1) supervisor.erl:414: :supervisor.do_start_child_i/3
            (stdlib 4.0.1) supervisor.erl:400: :supervisor.do_start_child/2
            (stdlib 4.0.1) supervisor.erl:384: anonymous fn/3 in :supervisor.start_children/2
            (stdlib 4.0.1) supervisor.erl:1250: :supervisor.children_map/4
            (stdlib 4.0.1) supervisor.erl:350: :supervisor.init_children/2

I’m probably missing a very obvious config option here so looking for help!

Thanks!

Same question also posted to SO: https://stackoverflow.com/questions/75249871/disable-oban-job-execution-on-a-node-with-oban-web-running