Your initial issue was likely due to the single connection being held by your job while oban tries to fetch more jobs or record heartbeats.
That’s correct. Oban uses one additional connection for pubsub notifications.
I typically use something like this in application.ex to prevent jobs running in an iex session:
defp oban_config do
opts = Application.get_env(:my_app, Oban)
if Code.ensure_loaded?(IEx) and IEx.started?() do
opts
|> Keyword.put(:crontab, false)
|> Keyword.put(:queues, false)
else
opts
end
end
