SETUP CRON To Delete File
how to remove logs in every 2 hours in Linux Terminal
below is my path where my log file is kept
/home/test/dev/sample.log
I want to set a cron so every 2 hours sample.log file will be delete.
can you please help me to set that cron in Linux terminal
0 */2 * * * <username> echo "" > /home/test/dev/sample.log
add in /etc/crontab, restart crontab service.
Or maybe it's better to use logrotate.
Related
I've modified the crontab with:
sudo crontab -e
and added a cron for a script to run every minute so I can test if it works:
1 * * * * /scripts/backup-script.sh > /scripts/backup-script.logs
Afterwards, I tried to restart the cron service to restart the server but the cron doesn't seem to be working, I tried to use:
crontab -l
and it appears to have the old content as if I didnt even modify it. However, going into crontab -e does show the updated content.
To make your script run every minute your cron record must be:
* * * * * /scripts/backup-script.sh > /scripts/backup-script.logs
What you enter will run every 1st minute every hour
And if you add record via crontab command you do not need to touch cron daemon
To see the cron record you add with sudo crontab -e you must check it with command sudo crontab -l. Otherwise you list cron record of different user
I am new to Linux and have a problem that I have tried to look online and could not find a solution
I have 4 scripts that are running in cron.d 3 of them I set to run every minute and they are fine and logging into the output files but the last one should run at 1:00 am but it will not.
-rw-r--r-- 1 root root 390 Jul 29 14:03 Test
* * * * * root /usr/sa/dir1/dir2/script1.sh >> /usr/sa/dir1/logs/fileoutput 2>&1
* * * * * root /usr/sa/dir1/dir2/script2.sh >> /usr/sa/dir1/logs/fileoutput 2>&1
* * * * * root /usr/sa/dir1/dir2/script3.sh >> /usr/sa/dir1/logs/fileoutput 2>&1
0 1 * * * root /usr/sa/dir1/dir2/script4.sh >> /usr/sa/dir1/logs/fileoutput 2>&1
I checked the permission and all seems to be fine as the same script from cron.d file are running as I can see entries from cron that are executed in /var/log/messages and same from the log files.
Things I have tried till now and worked
IF I vim the file and change for the 4th script to run every minute it runs fine.
IF I vim the file and change for the 4th script to run during the day it runs.
IF I include the script under crontab of root user and it runs ok.
IF I run script form the command line it runs ok.
I can not figure out why viming the file in cron.d the script will be executed by cron.
Thank you in advance for the help
Things I have tried till now and worked
IF I vim the file and change for the 4th script to run every minute it runs fine.
IF I vim the file and change for the 4th script to run during the day it runs.
IF I include the script under crontab of root user and it runs ok.
IF I run script form the command line it runs ok.
I can not figure out why viming the file in cron.d the script will be executed by cron.
I don't see errors in /var/log/messages
Are you commiting this crontab by just editing the raw file or are you using crontab <my-new-crontab>? If you aren't then try the latter. :)
I end it up adding the scripts to the crontab of the user root and seems to be ok.
I am running SUSE Linux as a non-root user (getting root access also will not be a possibility). I would like to have a .sh script I created be run daily.
My crontab looks like:
0 0 * * * * /path/to/file.sh
I also have a line return after this as per many troubleshooting suggestions. My script deletes files older than 14 days. I also added a means to log output to check whether the script runs.
However, the job does not run automatically. I also am not able to check /var/log/messages for any notifications on whether cron can run or not.
What am I doing wrong? How can I check if cron itself is running/can run for my user? Do I have to supply cron with any paths or environment variables?
The correct approach to run your cron every midnight is:
00 00 * * * /bin/bash path/to/your/script.sh >> /path/to/log/file.log
I have a very simple script in my crontab that I want to run every day. It is located in /home:
-rwxr-xr-x 1 root root 40 Apr 15 08:01 kill_slony_stop_sql.sh
It has execute permission and here is the content:
#!/bin/bash
slon_kill;rcpostgresql stop
and here is the cron line for it to run daily:
56 12 * * * /home/kill_slony_stop_sql.sh
But it is not working for some reason. When I type /home/kill_slony_stop_sql.sh in the command line, it works good but it is not working in the crontab.
Any thoughts?
It is most likely a PATH issue. Have a look at Why is my crontab not running and be sure to set a PATH so that it can call your slon_kill command.
Also, add some debug to your cron
56 12 * * * /home/kill_slony_stop_sql.sh &>/tmp/errorcron.log
And also look at the logs; cron logs its actions via syslog, which (depending on your setup) often go to /var/log/cron or /var/log/syslog.
I had the same problem with a daily cron job, I used the #daily but this will run at 00:00 every day.
#daily /usr/local/bin/msa70_check.sh
was the cron tab line i added, below is the script i run.
#!/bin/bash
# msa70 disk check
/sbin/mdadm --detail /dev/md0 /dev/md1|
/bin/mailx -s"Disk check on server123 please check" person#domain.com
I also had to edit my script and add /sbin/ and /bin in front of mdadm and mailx for the cron job to run
I'm using a Raspberry Pi for a status display, but for whatever reason it gets incredabbly sluggish after a day or so of running so I wanted to reboot it every day so I setup a cron job to do that every morning at 8:50. But, it doesn't seem to be working. Is there anything special about using cron to do a reboot?
This is my crontab for the root user:
# m h dom mon dow command
50 8 * * * shutdown now -r >> /var/log/cron.log
0,30 * * * * date >> /var/log/cron.log
The second line works just fine, but I can't seem to get the restart command to work. It doesn't even output anything to the log.
Try using the fully specified path to shutdown. date may be in the PATH in roots cron environment, /sbin may not be looked up.
You need to edit the root user crontab
sudo crontab -e
then..
50 8 * * * reboot
Save and exit.