Scheduler stops working sometimes

Questions
1

I have scheduler trigger workflow which should trigger every 2 hours. I used this cron expression: 0 */2 * * *

But as I saw in my executions, it triggered for like 2-3 intervals, but then completely stopped triggering every 2 hours.

And there is no error messages. The workflow simply didn’t trigger.

To test this fast, I have changed time interval to trigger every minute. And the same problem: it triggers for 4-5 interval attempts, but then stops working suddenly.

Here is the executions:

image
image2298×700 55 KB

Also, after activating the workflow in multiple projects, the scheduler triggered for some projects, and didn’t trigger for some at all.

By the way, the settings of timezone is America/New York

Information on my n8n setup

  • n8n version: 1.73.0
  • Database (default: SQLite): Postgres
  • Running n8n via (Docker, npm, n8n cloud, desktop app): Self-hosted Docker
2

Welcome to the community!

What if you put 0,2,4,6,8,10,12,14,16,18,20,22 instead of */2?
These would be explicit hours of a day and looks a bit too verbose but it wouldn’t be prone to over-23-hrs cron issue. Cron doesn’t manage intervals particularly well (and we do not actually know which version of cron is used by n8n behind the curtains).

3

You mean like this: 0 0,2,4,6,8,10,12,14,16,18,20,22 * * * ?

1 Like
4

Thank you for the response. I have changed the cron expression as you have described. I will let you know if this will solve my problem.

Now, how about scheduler not triggering for some projects, and not triggering for some projects at all?

5

I have a working schedule workflow that runs every minute (at the start of every minute).

I used this expression, and it works without any issues:

0 * * * * *

Can you try it?

6

I’m sorry, can’t really be of any help here. All of my workflows (just a few to be honest, simple and straightforward scheduling rules using cron notation) get triggered as expected. Maybe someone from n8n team could take a look into this.

1 Like
7

There is a whole big thread on this matter.

May be worth bookmarking and watching how things go there.

1 Like
8

Thank you.

9

Yep. Please let here know if this solves your issue, in a couple of days.

I will be wondering if this is the solid approach to solve the issues with failing Schedule triggers.

10

Thank you for your response.

Although it seems to be an invalid cron expression (I check it here: https://crontab.guru/), yes, it worked literally every 1 minute. But my objective is to make it trigger every two hours. But it is not working.

11

Okay, I have updated my node. I will let you know about the result soon. Thanks.

1 Like
12

Update: No, it didn’t work.

13

For testing, I have changed the interval to every 1 minute using this expression: * * * * *

It triggered for like 3-4 attempts every 1 minute. But after that, it returns this error:
ERROR 2025-03-20T16:10:00.001944Z Error: ERROR: You specified an invalid date. at CronTime.getNextDateFrom (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/[email protected]/node_modules/cron/dist/time.js:136:19) at CronTime.sendAt (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/[email protected]/node_modules/cron/dist/time.js:98:25) at CronTime.getTimeout (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/[email protected]/node_modules/cron/dist/time.js:110:34) at Timeout.callbackWrapper [as _onTimeout] (/u