Ubuntu 20.04 cron jobs doesn't work when a specific time was added

Question

I had a strange behavior in Ubuntu 20.04 cron job:

* * * * * echo "Hello world!" >> /tmp/hello.log 2>&1    <---working with logs
5 10 * * * echo "Hello world!" >> /tmp/hello.log 2>&1   <---doesn't working, no logs.

My another debian 11 are working fine with both time-set above.

The time/timezone, privilege are all good, any ideas?

Answer 1

It turns out I didn't restart cron service after I changed the timezone.

service cron restart

Solved the problem.