Received "The requested webhook "POST ..." is not registered

Describe the issue/error/question

A webhook I have published is not triggering. The webhook is active, and the workflow is active.

The debug logs shows a message:

[email protected]    | 2022-06-03T18:41:18.799Z | debug    | Received webhoook "POST" for path ".....71b88be3d83a" {"file":"ActiveWorkflowRunner.js","function":"executeWebhook"}

But completing a post request shows the response:

What is the error message (if any)?

I don’t see any other errors.

Information on your n8n setup

  • n8n version: 0.179.0
  • Database you’re using (default: SQLite): - Postgresql
  • Running n8n with the execution process [own(default), main]: default
  • Running n8n via [Docker, npm, n8n.cloud, desktop app]: Docker

Quick update - I think I diagnosed the issue. This is just a guess right now but here is what I think is happening.

We run n8n in docker swarm - which has the ability to start n8n in a separate container while an old instance is running, using the deploy.update_config.order = start-first Then, once the new n8n instance is running, docker would shut down the old one gracefully.

I believe this causes the webhooks to get disabled when the old instance gets shut down.

Yes, exactly that would cause it and is so very very likely the source of the problem you are facing. Two n8n processes are not allowed to overlap as the one that shuts down will delete the webhooks from the database. The remaining one would then be left without them and they would so not work.

What you can do to avoid that (next to changing the order-setting) would be to set the environment variable N8N_SKIP_WEBHOOK_DEREGISTRATION_SHUTDOWN=true. n8n will then not delete the webhooks on shutdown anymore.