pm2 doesnt work with crontab

chrisfr1976

Hi,

try this:

crontab -e with connected user:

05 20 * * * /usr/bin/pm2 start mm
15 07 * * * /usr/bin/pm2 start mm
30 21 * * * /usr/bin/pm2 stop mm

sudo crontab -e is not necessary.
I do not understand the start at 20:05 (first line)
my pm2 is in /usr/bin
always use full path in crontab

If you’re not sure where PM2 is you can use find / -iname pm2 in the console. Important is the full path in crontab.
/home/chris/.nvm/versions/node/v22.9.0/lib/node_modules/pm2/pm2 would be an alternative for me.

plainbroke

@chrisfr1976 said in pm2 doesnt work with crontab:

find / -iname pm2

/usr/local/bin/pm2
/usr/local/lib/node_modules/pm2
/usr/local/lib/node_modules/pm2/bin/pm2
/usr/local/lib/node_modules/pm2/lib/templates/logrotate.d/pm2
/usr/local/lib/node_modules/pm2/pm2


/home/pi/MagicMirror/node_modules/.bin/pm2
/home/pi/MagicMirror/node_modules/pm2
/home/pi/MagicMirror/node_modules/pm2/bin/pm2
/home/pi/MagicMirror/node_modules/pm2/lib/templates/logrotate.d/pm2
/home/pi/MagicMirror/node_modules/pm2/pm2

Which is the true one and one to use?

chrisfr1976

@plainbroke
Then use this:
/usr/local/bin/pm2

plainbroke

@chrisfr1976
@sdetweil
Thank you both for the help.
/usr/local/bin/pm2 restart mm
worked so I set it up to stop now and if (fingers crossed) works.
I am golden.
Wonder why I never had to use the full path before?
Maybe my pm2 path was /home/pi/pm2 before.
Doesn’t really matter as long as it works, I am a happy camper.
It works.
Thank you so much… I will mark this solved.
Well I would if I could… strange.

By the way " which pm2 " shows the path that I needed to use in crontab -e

sdetweil

@plainbroke awesome

i should have remembered the path problem

plainbroke

@sdetweil
Did the new MM and or trixie change the way crontab works? Mine has stopped working since the update to 2.33. I tried again tonight and will see if the changes work or not… also my mm.json file quit working. Hind sight is 20/20 should have left well enough alone…

sdetweil

@plainbroke I do not know

Sorry, I have to ask, you DID use a new sd card, right?

What does /var/log/syslog say about the crontab execution

Did you use crontab -e
Or sudo crontab -e

1st is run as user who executed the crontab command
2nd is run as root

plainbroke

@sdetweil
Using NVMe disk 256gb smallest I had on hand. 3 of them are exhibiting the same issues. I did try going back to Bookworm and I am still getthing a blank screen after a while. I ran npm run config:check it says all is good in the config.js ////
I am currently reloading from scratch.
Which OS is better for the 2.33 MM? 32 or 64 bit?
Wondering if I was using 32 bit and now the 64 bit is messing with me… So dang many things can mess with these little devices.

I only use crontab -e, should I try sudo crontab -e

sdetweil

@plainbroke no, without sudo is best

Maybe pm2 isn’t in the path when crontab fires
Check the syslog for crontab errors

32 bit is about to be trouble.

The latest nodejs version, 24, has dropped builds for 32 bit

plainbroke

@sdetweil
Thanks for the info I almost pulled down 32 bit.
It has been interesting to say the least going to trixie.
Turns out my problem was a failed NVMe drive.
I thought those things where supposed to last for a LONG long time…
I did get crontab -e to work with trixie and MM 2.33 not a fun ride, but entertaining. I finally learned how to use bash to make batch style files…
So not a complete loss of time…

sdetweil

@plainbroke technology is SOOOO much fun! Simple, til it’s not!

Thanks for the feedback. Others will ask, I’m sure they could use your help!

plainbroke

@sdetweil
Ok crontab -e worked last night to shutdown MM. So the pm2 stop all worked.
BUT this morning the pm2 restart mm did nothing.
I used find to get these:

/home/pi/MagicMirror/node_modules/.bin/pm2
/home/pi/MagicMirror/node_modules/pm2
/home/pi/MagicMirror/node_modules/pm2/bin/pm2
/home/pi/MagicMirror/node_modules/pm2/lib/templates/logrotate.d/pm2
/home/pi/MagicMirror/node_modules/pm2/pm2
/usr/local/bin/pm2
/usr/local/lib/node_modules/pm2
/usr/local/lib/node_modules/pm2/bin/pm2
/usr/local/lib/node_modules/pm2/lib/templates/logrotate.d/pm2
/usr/local/lib/node_modules/pm2/pm2

ANY idea on which one would work better.?
Here is my current crontab -e

# Turn off display at 9pm
00 21 * * 0-6 /usr/local/bin/pm2 stop all >/dev/null >2&1
# Turn on screen Monday - Friday at 6:45 am
45 06 * * 1-5 /usr/local/bin/pm2 start mm >/dev/null >2&1
# Turn on screen Saturday - Sunday at 7:30 am
30 07 * * 6,0 /usr/local/bin/pm2 start mm >/dev/null >2&1

sdetweil

@plainbroke which one, if any , are in the path
Are they all executable?

ls -laF
Will give you the permissions mask

Are any of them links to another?

What changed?

/usr/local/bin/pm2
Should be the one

sdetweil

@plainbroke also look in /var/log/syslog
To find the logging of the execute at the time it should fire

plainbroke

@sdetweil
Weird, I do not have /var/log/syslog.
Even did a find for it nothing, popped up…

pi@Pixie:~ $ ls -laF
total 348
drwx------ 15 pi   pi     4096 Nov 10 15:36 ./
drwxr-xr-x  3 root root   4096 Sep 30 19:18 ../
-rw-------  1 pi   pi     9080 Nov 10 13:17 .bash_history
-rw-r--r--  1 pi   pi      220 Sep 30 19:06 .bash_logout
-rw-r--r--  1 pi   pi     3523 Sep 30 19:06 .bashrc
drwx------ 13 pi   pi     4096 Nov  7 18:22 .cache/
drwx------ 22 pi   pi     4096 Nov  8 12:57 .config/
drwx------  3 pi   pi     4096 Nov  7 17:49 .dbus/
drwxrwxr-x  2 pi   pi     4096 Sep 30 19:17 Desktop/
drwx------  2 pi   pi     4096 Nov  7 23:11 Documents/
-rw-rw-r--  1 pi   pi        0 Nov  7 20:00 .gitconfig
-rw-rw-r--  1 pi   pi       81 Nov  7 18:24 .gtkrc-2.0
-rw-rw-r--  1 pi   pi   222126 Oct 27 18:52 install.log
drwx------  4 pi   pi     4096 Sep 30 19:18 .local/
drwxrwxr-x 16 pi   pi     4096 Nov  8 12:54 MagicMirror/
-rwxrwxrwx  1 pi   pi      320 Jun 12  2022 mm.json*
-rwxrwxrwx  1 pi   pi       38 Jul 16  2023 mm.sh*
drwx------  4 pi   pi     4096 Nov  6 21:05 .mozilla/
drwxrwxr-x  4 pi   pi     4096 Oct 27 18:30 .npm/
drwx------  3 pi   pi     4096 Oct 27 18:52 .pki/
drwxrwxr-x  5 pi   pi     4096 Nov  9 17:24 .pm2/
-rw-r--r--  1 pi   pi      807 Sep 30 19:06 .profile
-rw-rw-r--  1 pi   pi       66 Oct 27 19:22 .selected_editor
drwxrwxr-x  4 pi   pi     4096 Nov 10 15:43 shared/
-rw-r--r--  1 pi   pi        0 Sep 30 19:18 .sudo_as_admin_successful
drwx------  3 pi   pi     4096 Nov  5 17:30 .vnc/
-rw-------  1 pi   pi       50 Nov  9 17:24 .Xauthority
-rw-------  1 pi   pi     8238 Nov  9 19:32 .xsession-errors
-rw-------  1 pi   pi     7945 Nov  9 17:24 .xsession-errors.old

mumblebaj

@plainbroke Instead of piping the output to a blackhole, maybe pipe it to a logfile which you can interrogate to see why the pm2 start is not working?

evroom

About /var/log/syslog.
Debian does not use that anymore, already since a while.
As far as I understand it, you will need to get familiar with journalctl.
For cron jobs try this:

$ journalctl --since "1 hour ago" --unit cron.service

$ journalctl -f -u cron.service

Happy hunting.

plainbroke

@evroom,
I get that nothing is found, when I run either of your suggestions.

@mumblebaj
Explain piping, Please…

sdetweil

@plainbroke piping is a technique of stitching together multiple commands to accomplish a task

The vertical bar is called the pipe character
Which takes the output of the left side and presents it as input to the right side , so its like forming a pipe

When I want to find all the MagicMirror processes running in the background I do this

ps -ef

This give the processes and the command line used to start them
But is a lot of data

So I can filter that with grep , and I can pass in data on its stdin

ps -ef | grep -i MagicMirror

That gives just the rows of the process list with MagicMirror on them

But if I want to kill them I need the process id on each row
That’s the second value on each row
I can use the awk command to get that

ps -ef | grep -i MagicMirror | awk ‘{ print $2}’

Now I have the process ids and can issue the kill command with them

ps -ef | grep -i MagicMirror | awk ‘{ print $2}’ |  xargs sudo  kill -9

evroom

@plainbroke said in pm2 doesnt work with crontab:

@evroom,
I get that nothing is found, when I run either of your suggestions.

The journalctl -f shows the current activities.
Simular to tail -f <filename>.
So when there are none, you will see none.
Use that when you know that a cron job is going to occur anytime soon.
The --since "1 hour ago" searches for activities in the last hour.
Change to, for example --since "24 hours ago" for activities in the last 24 hours.
When nothing comes out, then indeed nothing happened (during the time period you are searching in).

Other --since options:

"today"
"00:20"
"2025-11-12"
"2025-11-12 07:30:00"