Function timeouts related to GET http://127.0.0.1:41888/MSI/token

Question

I've noticed some queue items getting dropped in the poison queue, and after investigating through App Insights, the following pattern shows repeatedly:

I've searched around and don't see any answers as to why this is happening or what could be causing the delay. Does anyone have any ideas?

Answer 1

Hi Michael,

Welcome to the community.

You get a 401 from the Key Vault in your screenshot.

401 means that the request is unauthenticated for Key Vault.

A request is authenticated if:

• The key vault knows the identity of the caller; and
• The caller is allowed to try to access Key Vault resources.

source: https://learn.microsoft.com/en-us/azure/key-vault/general/rest-error-codes

The function then times out after 5 minutes, which is expected behavior:

source : https://learn.microsoft.com/en-us/azure/azure-functions/functions-scale#timeout

Check the Key Vault logs as well as the function code to further diagnose.

Answer 2

@Raiford, Michael The FunctionTimeoutException in your logs is about your function hitting the function app timeout of 5 min. You could try configuring a longer timeout (max of 10 minutes for the consumption tier).