Azure function is not triggering on scheduled time

Question

Note: Even though it may seem duplicate, My issue is different and I request you to read complete description before hastily marking the question down just by reading Question title.

I opened "Azure function is not triggering on scheduled time " issue on official "azure-webjobs-sdk-script" git repository on May 24, 2017-but there is no reply yet. So I am re-asking this here.

I am using azure function in consumption plan, and have scheduled it to execute at every 4.00 am utc by setting following cron expression in function.json:

{  

"bindings": [
    {
      "name": "myTimer",
      "type": "timerTrigger",
      "direction": "in",
      "schedule": "0 0 4 * * *"
    }
  ],
  "disabled": false
}

Azure function does get execute on time only if I am logged into portal or clicks on function blade. It does not invoke when I am logged out from portal (suggesting either system listener or function go to sleep after some interval).

Their official documentation states that functions in consumption plan do not require any other settings (like Always on) to keep the function alive, instances of the Azure Functions host are dynamically added and removed based on the number of incoming events.. So as per documentation, no other settings I have to configure to execute function in consumption plan.

What I have tried?

1. From "Timer triggered azure function not getting triggered" question on SO, I re-checked and ensured my plan (consumption plan) and time zone. (I want it to run in utc, so no explicit setting is required)

2. From "#1445: Azure function timer trigger not firing" git issue, I checked whether it was just logs that are not appearing. But I am certainly sure, that its not the logs but the actual function does not get triggered unless I am having my portal on or trigger it manually.

3. I tried to check whether this behavior exists if I change the schedule to a more closer recursive invocations--I scheduled function to get executed at every 2 hours, and this schedule perfectly worked even when I logged out or did not awake function manually. This means, there is some issue when schedule is set to run on larger set of intervals (in my case each day)

Answer 1

As discussed here in #1534, deleting and redeploying the function completely in new function app did not reproduce the issue. So deleting the function and/or function app-and redeploying the same should make things working. Meanwhile, Azure team has announced to add internal logging which will help future diagnosis.