Azure Function App - Timer trigger not firing

Question

Hello,

We have a Function App with a single Timer trigger.
It is hosted on an App Service Plan (P1v2).
We have Always On enabled on the Function App.
We are using Runtime v4 (only option?).
We don't have a time zone specified, but the predicted schedule is as we expect:
2022-11-24T12:43:02.639 [Information] The next 5 occurrences of the 'Redacted' schedule (Cron: '0 1 * * *') will be:
11/25/2022 01:00:00Z
11/26/2022 01:00:00Z
11/27/2022 01:00:00Z
11/28/2022 01:00:00Z
11/29/2022 01:00:00Z

We deploy the app through devops using zipdeploy

2022-11-25T13:13:47Z [Information] Executing 'Redacted' (Reason='This function was programmatically called via the host APIs.', Id=973dceb0-ee73-4848-aa60-d335afa6511c)

Function App is hosted in west-europe.

Answer 1

@Mathia Van De Poel Thanks for reaching out. Azure Functions uses the NCronTab library to interpret NCRONTAB expressions. NCRONTAB expression supports both five field and six field formats. The sixth field position is a value for seconds which is placed at the beginning of the expression. For more details you can refer to this document.

Please confirm if you are using the five or six field formats as per information it looks like your expression is 0 1 *
You should leverage 0 0 1 * * * so it executes your function app at 1:00 am UTC every day. In case if you already using the five field and six field formats then I will suggest you to navigate to the Diagnose and solve problems to check if there was any exception/error while executing your function app.