cron job decides for itself if it wants to run
I recently wrote a python script that reminds me via email if I need to move my car for the street sweeper mafia (and avoid a ticket). When I ran the script from the command line, it worked every time. So I added it to crontab -e and tested it, it worked if I reset the date, time, etc.
I decided to run the cron tab every hour just for debug purposes:
1 * * * * python3 /home/robert/scripts/parking-project.py
On the night last week when the python script should have triggered the email, I was ready for the reminder. Instead there was no action.
I researched several cronjob articles to see how I messed up, but they all reinforced my original implementation decisions.
Eventually I got distracted and started working on other projects, but then today, out of the blue, my cronjob started working exactly like I expected it to.
more info
I had restarted the machine many times since implementing the job - so a reboot was not the answer.
my clock was correct
the script worked perfectly if you copied and pasted the command that was listed in crontab -e
journalctl -u cron.servicereported that there was never any attempt to run the cronjobinternet access was not a factor
What could have made the cronjob suddenly decide to start working correctly?
18.04 bash scripts python cron
edited Feb 20 at 18:31
pa4080
14.8k52872
asked Feb 19 at 23:21
Robert BakerRobert Baker
8210
add a comment |
I recently wrote a python script that reminds me via email if I need to move my car for the street sweeper mafia (and avoid a ticket). When I ran the script from the command line, it worked every time. So I added it to crontab -e and tested it, it worked if I reset the date, time, etc.
I decided to run the cron tab every hour just for debug purposes:
1 * * * * python3 /home/robert/scripts/parking-project.py
On the night last week when the python script should have triggered the email, I was ready for the reminder. Instead there was no action.
I researched several cronjob articles to see how I messed up, but they all reinforced my original implementation decisions.
Eventually I got distracted and started working on other projects, but then today, out of the blue, my cronjob started working exactly like I expected it to.
more info
I had restarted the machine many times since implementing the job - so a reboot was not the answer.
my clock was correct
the script worked perfectly if you copied and pasted the command that was listed in crontab -e
journalctl -u cron.servicereported that there was never any attempt to run the cronjobinternet access was not a factor
What could have made the cronjob suddenly decide to start working correctly?
18.04 bash scripts python cron
edited Feb 20 at 18:31
pa4080
14.8k52872
asked Feb 19 at 23:21
Robert BakerRobert Baker
8210
1
Was your system, by chance, suspended/hibernated/off or simply logged off during the periods that the cronjobs did not run?
– user535733
Feb 19 at 23:30
@user535733, yes, but not always. There were plenty of times when it should have run when it was online but didn't. I don't think this was a factor, but thank you for jumping in.
– Robert Baker
Feb 19 at 23:31
1
wouldn't1 * * * *mean the first minute of every hour? Remember, the notation is MM HH, not HH MM. Some versions of cron also require a username such as00 01 * * * root /home/robert/scripts/parking-project.py. My server performs a bulk processing of security footage with a crontab, and it looks like this (ubuntu 16.04)30 2 * * * root bash /mnt/array0/porch/process.sh
– Minty
Feb 20 at 2:25
3
@Minty OP said "run [...] every hour", so that line is OK. The user crontab edited usingcrontab -edoesn't require a username (those commands run as your user). The username is required in system crontab files (/etc/cronatb,/etc/cron.d/*).
– Olorin
Feb 20 at 3:55
add a comment |
I recently wrote a python script that reminds me via email if I need to move my car for the street sweeper mafia (and avoid a ticket). When I ran the script from the command line, it worked every time. So I added it to crontab -e and tested it, it worked if I reset the date, time, etc.
I decided to run the cron tab every hour just for debug purposes:
1 * * * * python3 /home/robert/scripts/parking-project.py
On the night last week when the python script should have triggered the email, I was ready for the reminder. Instead there was no action.
I researched several cronjob articles to see how I messed up, but they all reinforced my original implementation decisions.
Eventually I got distracted and started working on other projects, but then today, out of the blue, my cronjob started working exactly like I expected it to.
more info
I had restarted the machine many times since implementing the job - so a reboot was not the answer.
my clock was correct
the script worked perfectly if you copied and pasted the command that was listed in crontab -e
journalctl -u cron.servicereported that there was never any attempt to run the cronjobinternet access was not a factor
What could have made the cronjob suddenly decide to start working correctly?
18.04 bash scripts python cron
edited Feb 20 at 18:31
pa4080
14.8k52872
asked Feb 19 at 23:21
Robert BakerRobert Baker
8210
I recently wrote a python script that reminds me via email if I need to move my car for the street sweeper mafia (and avoid a ticket). When I ran the script from the command line, it worked every time. So I added it to crontab -e and tested it, it worked if I reset the date, time, etc.
I decided to run the cron tab every hour just for debug purposes:
1 * * * * python3 /home/robert/scripts/parking-project.py
On the night last week when the python script should have triggered the email, I was ready for the reminder. Instead there was no action.
I researched several cronjob articles to see how I messed up, but they all reinforced my original implementation decisions.
Eventually I got distracted and started working on other projects, but then today, out of the blue, my cronjob started working exactly like I expected it to.
more info
I had restarted the machine many times since implementing the job - so a reboot was not the answer.
my clock was correct
the script worked perfectly if you copied and pasted the command that was listed in crontab -e
journalctl -u cron.servicereported that there was never any attempt to run the cronjobinternet access was not a factor
What could have made the cronjob suddenly decide to start working correctly?
18.04 bash scripts python cron
18.04 bash scripts python cron
edited Feb 20 at 18:31
pa4080
14.8k52872
asked Feb 19 at 23:21
Robert BakerRobert Baker
8210
edited Feb 20 at 18:31
pa4080
14.8k52872
asked Feb 19 at 23:21
Robert BakerRobert Baker
8210
edited Feb 20 at 18:31
pa4080
14.8k52872
edited Feb 20 at 18:31
pa4080
14.8k52872
edited Feb 20 at 18:31
pa4080
14.8k52872
14.8k52872
asked Feb 19 at 23:21
Robert BakerRobert Baker
8210
asked Feb 19 at 23:21
Robert BakerRobert Baker
8210
asked Feb 19 at 23:21
Robert BakerRobert Baker
8210
8210
1
Was your system, by chance, suspended/hibernated/off or simply logged off during the periods that the cronjobs did not run?
– user535733
Feb 19 at 23:30
@user535733, yes, but not always. There were plenty of times when it should have run when it was online but didn't. I don't think this was a factor, but thank you for jumping in.
– Robert Baker
Feb 19 at 23:31
1
wouldn't1 * * * *mean the first minute of every hour? Remember, the notation is MM HH, not HH MM. Some versions of cron also require a username such as00 01 * * * root /home/robert/scripts/parking-project.py. My server performs a bulk processing of security footage with a crontab, and it looks like this (ubuntu 16.04)30 2 * * * root bash /mnt/array0/porch/process.sh
– Minty
Feb 20 at 2:25
3
@Minty OP said "run [...] every hour", so that line is OK. The user crontab edited usingcrontab -edoesn't require a username (those commands run as your user). The username is required in system crontab files (/etc/cronatb,/etc/cron.d/*).
– Olorin
Feb 20 at 3:55
add a comment |
1
Was your system, by chance, suspended/hibernated/off or simply logged off during the periods that the cronjobs did not run?
– user535733
Feb 19 at 23:30
@user535733, yes, but not always. There were plenty of times when it should have run when it was online but didn't. I don't think this was a factor, but thank you for jumping in.
– Robert Baker
Feb 19 at 23:31
1
wouldn't1 * * * *mean the first minute of every hour? Remember, the notation is MM HH, not HH MM. Some versions of cron also require a username such as00 01 * * * root /home/robert/scripts/parking-project.py. My server performs a bulk processing of security footage with a crontab, and it looks like this (ubuntu 16.04)30 2 * * * root bash /mnt/array0/porch/process.sh
– Minty
Feb 20 at 2:25
3
@Minty OP said "run [...] every hour", so that line is OK. The user crontab edited usingcrontab -edoesn't require a username (those commands run as your user). The username is required in system crontab files (/etc/cronatb,/etc/cron.d/*).
– Olorin
Feb 20 at 3:55
1
1
Was your system, by chance, suspended/hibernated/off or simply logged off during the periods that the cronjobs did not run?
– user535733
Feb 19 at 23:30
Was your system, by chance, suspended/hibernated/off or simply logged off during the periods that the cronjobs did not run?
– user535733
Feb 19 at 23:30
@user535733, yes, but not always. There were plenty of times when it should have run when it was online but didn't. I don't think this was a factor, but thank you for jumping in.
– Robert Baker
Feb 19 at 23:31
@user535733, yes, but not always. There were plenty of times when it should have run when it was online but didn't. I don't think this was a factor, but thank you for jumping in.
– Robert Baker
Feb 19 at 23:31
1
1
wouldn't
1 * * * * mean the first minute of every hour? Remember, the notation is MM HH, not HH MM. Some versions of cron also require a username such as 00 01 * * * root /home/robert/scripts/parking-project.py. My server performs a bulk processing of security footage with a crontab, and it looks like this (ubuntu 16.04) 30 2 * * * root bash /mnt/array0/porch/process.sh– Minty
Feb 20 at 2:25
wouldn't
1 * * * * mean the first minute of every hour? Remember, the notation is MM HH, not HH MM. Some versions of cron also require a username such as 00 01 * * * root /home/robert/scripts/parking-project.py. My server performs a bulk processing of security footage with a crontab, and it looks like this (ubuntu 16.04) 30 2 * * * root bash /mnt/array0/porch/process.sh– Minty
Feb 20 at 2:25
3
3
@Minty OP said "run [...] every hour", so that line is OK. The user crontab edited using
crontab -e doesn't require a username (those commands run as your user). The username is required in system crontab files (/etc/cronatb, /etc/cron.d/*).– Olorin
Feb 20 at 3:55
@Minty OP said "run [...] every hour", so that line is OK. The user crontab edited using
crontab -e doesn't require a username (those commands run as your user). The username is required in system crontab files (/etc/cronatb, /etc/cron.d/*).– Olorin
Feb 20 at 3:55
add a comment |
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1
Was your system, by chance, suspended/hibernated/off or simply logged off during the periods that the cronjobs did not run?
– user535733
Feb 19 at 23:30
@user535733, yes, but not always. There were plenty of times when it should have run when it was online but didn't. I don't think this was a factor, but thank you for jumping in.
– Robert Baker
Feb 19 at 23:31
1
wouldn't
1 * * * *mean the first minute of every hour? Remember, the notation is MM HH, not HH MM. Some versions of cron also require a username such as00 01 * * * root /home/robert/scripts/parking-project.py. My server performs a bulk processing of security footage with a crontab, and it looks like this (ubuntu 16.04)30 2 * * * root bash /mnt/array0/porch/process.sh– Minty
Feb 20 at 2:25
3
@Minty OP said "run [...] every hour", so that line is OK. The user crontab edited using
crontab -edoesn't require a username (those commands run as your user). The username is required in system crontab files (/etc/cronatb,/etc/cron.d/*).– Olorin
Feb 20 at 3:55