Cron runs only once instead every minute
I'm trying to run a script every minute (on a Docker container running Ubuntu 16.04)
The /etc/echo.sh simply echo the word "hi"
cat /etc/crontab
* * * * * root /etc/echo.sh > /var/log/cron.log 2>&1
/etc/init.d/cron reload
* Reloading configuration files for periodic command scheduler cron [ OK ]
tail -f /var/log/cron.log
hi
After printing "hi" once, nothing happens anymore.
Any ideas why?
cron docker ubuntu-16.04 crontab
asked 7 hours ago
SigSig
20628
add a comment |
I'm trying to run a script every minute (on a Docker container running Ubuntu 16.04)
The /etc/echo.sh simply echo the word "hi"
cat /etc/crontab
* * * * * root /etc/echo.sh > /var/log/cron.log 2>&1
/etc/init.d/cron reload
* Reloading configuration files for periodic command scheduler cron [ OK ]
tail -f /var/log/cron.log
hi
After printing "hi" once, nothing happens anymore.
Any ideas why?
cron docker ubuntu-16.04 crontab
asked 7 hours ago
SigSig
20628
add a comment |
I'm trying to run a script every minute (on a Docker container running Ubuntu 16.04)
The /etc/echo.sh simply echo the word "hi"
cat /etc/crontab
* * * * * root /etc/echo.sh > /var/log/cron.log 2>&1
/etc/init.d/cron reload
* Reloading configuration files for periodic command scheduler cron [ OK ]
tail -f /var/log/cron.log
hi
After printing "hi" once, nothing happens anymore.
Any ideas why?
cron docker ubuntu-16.04 crontab
asked 7 hours ago
SigSig
20628
I'm trying to run a script every minute (on a Docker container running Ubuntu 16.04)
The /etc/echo.sh simply echo the word "hi"
cat /etc/crontab
* * * * * root /etc/echo.sh > /var/log/cron.log 2>&1
/etc/init.d/cron reload
* Reloading configuration files for periodic command scheduler cron [ OK ]
tail -f /var/log/cron.log
hi
After printing "hi" once, nothing happens anymore.
Any ideas why?
cron docker ubuntu-16.04 crontab
cron docker ubuntu-16.04 crontab
asked 7 hours ago
SigSig
20628
asked 7 hours ago
SigSig
20628
asked 7 hours ago
SigSig
20628
asked 7 hours ago
SigSig
20628
asked 7 hours ago
SigSig
20628
20628
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
The script does run every minute but > truncates the file each time.
If the file does not exist, it shall be created; otherwise, it shall be truncated to be an empty file after being opened.
(source)
Use >> instead to append to the file.
answered 6 hours ago
Kamil MaciorowskiKamil Maciorowski
26.6k155681
Won'ttailsaytail: cron.log: file truncatedif the file is truncated? Or am I misunderstanding how tail works
– Ferrybig
3 hours ago
@Ferrybig Iftailnotices the short moment between truncating and placinghiback, then it will. In my Kubuntuecho hi > cron.logtriggers the message fromtailin about half the cases. It's a race condition so your (and the OP's) mileage may vary.
– Kamil Maciorowski
3 hours ago
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
The script does run every minute but > truncates the file each time.
If the file does not exist, it shall be created; otherwise, it shall be truncated to be an empty file after being opened.
(source)
Use >> instead to append to the file.
answered 6 hours ago
Kamil MaciorowskiKamil Maciorowski
26.6k155681
Won'ttailsaytail: cron.log: file truncatedif the file is truncated? Or am I misunderstanding how tail works
– Ferrybig
3 hours ago
@Ferrybig Iftailnotices the short moment between truncating and placinghiback, then it will. In my Kubuntuecho hi > cron.logtriggers the message fromtailin about half the cases. It's a race condition so your (and the OP's) mileage may vary.
– Kamil Maciorowski
3 hours ago
add a comment |
The script does run every minute but > truncates the file each time.
If the file does not exist, it shall be created; otherwise, it shall be truncated to be an empty file after being opened.
(source)
Use >> instead to append to the file.
answered 6 hours ago
Kamil MaciorowskiKamil Maciorowski
26.6k155681
Won'ttailsaytail: cron.log: file truncatedif the file is truncated? Or am I misunderstanding how tail works
– Ferrybig
3 hours ago
@Ferrybig Iftailnotices the short moment between truncating and placinghiback, then it will. In my Kubuntuecho hi > cron.logtriggers the message fromtailin about half the cases. It's a race condition so your (and the OP's) mileage may vary.
– Kamil Maciorowski
3 hours ago
add a comment |
The script does run every minute but > truncates the file each time.
If the file does not exist, it shall be created; otherwise, it shall be truncated to be an empty file after being opened.
(source)
Use >> instead to append to the file.
answered 6 hours ago
Kamil MaciorowskiKamil Maciorowski
26.6k155681
The script does run every minute but > truncates the file each time.
If the file does not exist, it shall be created; otherwise, it shall be truncated to be an empty file after being opened.
(source)
Use >> instead to append to the file.
answered 6 hours ago
Kamil MaciorowskiKamil Maciorowski
26.6k155681
edited 4 hours ago
answered 6 hours ago
Kamil MaciorowskiKamil Maciorowski
26.6k155681
answered 6 hours ago
Kamil MaciorowskiKamil Maciorowski
26.6k155681
answered 6 hours ago
Kamil MaciorowskiKamil Maciorowski
26.6k155681
26.6k155681
Won'ttailsaytail: cron.log: file truncatedif the file is truncated? Or am I misunderstanding how tail works
– Ferrybig
3 hours ago
@Ferrybig Iftailnotices the short moment between truncating and placinghiback, then it will. In my Kubuntuecho hi > cron.logtriggers the message fromtailin about half the cases. It's a race condition so your (and the OP's) mileage may vary.
– Kamil Maciorowski
3 hours ago
add a comment |
Won'ttailsaytail: cron.log: file truncatedif the file is truncated? Or am I misunderstanding how tail works
– Ferrybig
3 hours ago
@Ferrybig Iftailnotices the short moment between truncating and placinghiback, then it will. In my Kubuntuecho hi > cron.logtriggers the message fromtailin about half the cases. It's a race condition so your (and the OP's) mileage may vary.
– Kamil Maciorowski
3 hours ago
Won't
tail say tail: cron.log: file truncated if the file is truncated? Or am I misunderstanding how tail works– Ferrybig
3 hours ago
Won't
tail say tail: cron.log: file truncated if the file is truncated? Or am I misunderstanding how tail works– Ferrybig
3 hours ago
@Ferrybig If
tail notices the short moment between truncating and placing hi back, then it will. In my Kubuntu echo hi > cron.log triggers the message from tail in about half the cases. It's a race condition so your (and the OP's) mileage may vary.– Kamil Maciorowski
3 hours ago
@Ferrybig If
tail notices the short moment between truncating and placing hi back, then it will. In my Kubuntu echo hi > cron.log triggers the message from tail in about half the cases. It's a race condition so your (and the OP's) mileage may vary.– Kamil Maciorowski
3 hours ago
add a comment |
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