I have a script that checks if the PPTP VPN is running, and if not it reconnects the PPTP VPN. When I run the script manually it executes fine, but when I make a cron job, it's not running.
* * * * * /bin/bash /var/scripts/vpn-check.sh
Here is the script:
#!/bin/sh
/bin/ping -c3 192.168.17.27 > /tmp/pingreport
result=`grep "0 received" /tmp/pingreport`
truncresult="`echo "$result" | sed 's/^\(.................................\).*$$'`"
if [[ $truncresult == "3 packets transmitted, 0 received" ]]; then
/usr/sbin/pppd call home
fi
finally i found a solution ... instead of entering the cronjob with
crontab -e
i needed to edit the crontab file directly
nano /etc/crontab
adding e.g. something like
*/5 * * * * root /bin/bash /var/scripts/vpn-check.sh
and its fine now!
Thank you all for your help ... hope my solution will help other people as well.
After a long time getting errors, I just did this:
SHELL=/bin/bash
PATH=/bin:/sbin:/usr/bin:/usr/sbin
* * * * * /bin/bash /home/joaovitordeon/Documentos/test.sh
Where test.sh contains:
#!/bin/bash
/usr/bin/python3 /home/joaovitordeon/Documentos/test.py;
In my case, the issue was that the script wasn't marked as executable. To make sure it is, run the following command:
chmod +x your_script.sh
If you're positive the script runs outside of cron, execute
printf "SHELL=$SHELL\nPATH=$PATH\n* * * * * /bin/bash /var/scripts/vpn-check.sh\n"
Do crontab -e for whichever crontab you're using and replace it with output of the above command. This should mirror most of your environment in case there is some missing path issue or something else. Also check logs for any errors it's getting.
Though it definitly looks like the script has an error or you messed something up when copying it here
sed: -e expression #1, char 44: unterminated `s' command
./bad.sh: 5: ./bad.sh: [[: not found
Simple alternate script
#!/bin/bash
if [[ $(ping -c3 192.168.17.27) == *"0 received"* ]]; then
/usr/sbin/pppd call home
fi
Your script can be corrected and simplified like this:
#!/bin/sh
log=/tmp/vpn-check.log
{ date; ping -c3 192.168.17.27; } > $log
if grep -q '0 received' $log; then
/usr/sbin/pppd call home >>$log 2>&1
fi
Through our discussion in comments we confirmed that the script itself works, but pppd doesn't, when running from cron. This is because something must be different in an interactive shell like your terminal window, and in cron. This kind of problem is very common by the way.
The first thing to do is try to remember what configuration is necessary for pppd. I don't use it so I don't know. Maybe you need to set some environment variables? In which case most probably you set something in a startup file, like .bashrc, which is usually not used in a non-interactive shell, and would explain why pppd doesn't work.
The second thing is to check the logs of pppd. If you cannot find the logs easily, look into its man page, and it's configuration files, and try to find the logs, or how to make it log. Based on the logs, you should be able to find what is missing when running in cron, and resolve your problem.
Was having a similar problem that was resolved when a sh was put before the command in crontab
This did not work :
#reboot ~myhome/mycommand >/tmp/logfile 2>&1
This did :
#reboot sh ~myhome/mycommand >/tmp/logfile 2>&1
my case:
crontab -e
then adding the line:
* * * * * ( cd /directory/of/script/ && /bin/sh /directory/of/script/scriptItself.sh )
in fact, if I added "root" as per the user, it thought "root" was a command, and it didn't work.
As a complement of other's answers, didn't you forget the username in your crontab script ?
Try this :
* * * * * root /bin/bash /var/scripts/vpn-check.sh
EDIT
Here is a patch of your code
#!/bin/sh
/bin/ping -c3 192.168.17.27 > /tmp/pingreport
result=`grep "0 received" /tmp/pingreport`
truncresult=`echo "$result" | /bin/sed 's/^\(.................................\).*$/\1/'`
if [[ $truncresult == "3 packets transmitted, 0 received" ]]; then
/usr/sbin/pppd call home
fi
In my case, it could be solved by using this:
* * * * * root ( cd /directory/of/script/ && /directory/of/script/scriptItself.sh )
I used some ./folder/-references in the script, which didn't work.
The problem statement is script is getting executed when run manually in the shell but when run through cron, it gives "java: command not found" error -
Please try below 2 options and it should fix the issue -
Ensure the script is executable .If it's not, execute below -
chmod a+x your_script_name.sh
The cron job doesn’t run with the same user with which you are executing the script manually - so it doesn't have access to the same $PATH variable as your user which means it can't locate the Java executable to execute the commands in the script. We should first fetch the value of PATH variable as below and then set it(export) in the script -
echo $PATH can be used to fetch the value of PATH variable.
and your script can be modified as below - Please see second line starting with export
#!/bin/sh
export PATH=<provide the value of echo $PATH>
/bin/ping -c3 192.168.17.27 > /tmp/pingreport
result=`grep "0 received" /tmp/pingreport`
truncresult="`echo "$result" | sed 's/^\(.................................\).*$$'`"
if [[ $truncresult == "3 packets transmitted, 0 received" ]]; then
/usr/sbin/pppd call home
fi
First of all, check if cron service is running. You know the first question of the IT helpdesk: "Is the PC plugged in?".
For me, this was happening because the cronjob was executing from /root directory but my shell script (a script to pull the latest code from GitHub and run the tests) were in a different directory. So, I had to edit my script to have a cd to my scripts folder. My debug steps were
Verified that my script run independent of cron job
Checked /var/log/cron to see if the cron jobs are running. Verified that the job is running at the intended time
Added an echo command to the script to log the start and end times to a file. Verified that those were getting logged but not the actual commands
Logged the result of pwd to the same file and saw that the commands were getting executed from /root
Tried adding a cd to my script directory as the first line in the script. When the cron job kicked off this time, the script got executed just like in step 1.
it was timezone in my case. I scheduled cron with my local time but server has different timezone and it does not run at all. so make sure your server has same time by date cmd
first run command env > env.tmp
then run cat env.tmp
copy PATH=.................. Full line and paste into crontab -e, line before your cronjobs.
try this
/home/your site folder name/public_html/gistfile1.sh
set cron path like above
I want to automatically start a program if it crashes (check if the process exists, if not, restart it), so using crontab is a simple solution, but
I creatd a simple crontab task using crontab -e or in /etc/crontab file like this:
* * * * * /usr/bin/gnome-terminal
it doesn't work, it never launches gnome-terminal, I can see it executes the task in /var/log/syslog (Ubuntu) or /var/log/cron (CentOS), the gnome-terminal never comes up.
if you say since gnome-terminal is a gui program, then, this script to create bluetooth service won't work either :
using crontab -e or /etc/crontab:
* * * * * /home/username/run-bt
run-bt:
#!/bin/sh
# find bt pid
/usr/bin/pgrep bluetoothd
# if not running
if [ $? -ne 0 ]
then
/usr/sbin/service bluetooth restart
fi⏎
I already made the run-bt script executable, but bluetooth service won't start even if I stop the bluetooth service manually.
but this:
* * * * * /bin/ls > /tmp/ls.output
works as expected.
What's wrong?
Actually crontab does not load all the environment variables of the current user it runs for, just a few of them.
Maybe some of those environment variables are required by the scripts you try to run?
I'm trying to make a crontab with crontab -e, but it saves it in tmp/crontab.FTt6nI/crontab
the crons don't work so I guess that's the problem. But I don't understand why.
type:
crontab -l
to show list of crontab, your newly added crontab should be on the list. you could set the crontab to email the output to you by > youremail#aaa.com, in this way you can assure the cronjob is already run.
example:
* * * * * /usr/bin/php /home/username/public_html/cron.php > aaa#aaa.com
make sure the crond is running:
/etc/init.d/crond status
if it down, start it (centos/rhel):
/etc/init.d/crond start
debian/ubuntu:
/etc/init.d/cron start
hope that help.
I want to start pppd whenever it disconnects. I am trying to setup a shell script to run every 1 minute to see if it's down and reconnect.
I have a bash script called vpn-check.sh:
ping -c3 10.8.3.0 > pingreport
result=`grep "0 received" pingreport`
truncresult="`echo "$result" | sed 's/^\(.................................\).*$/\1/'`"
if [[ $truncresult == "3 packets transmitted, 0 received" ]]; then
pon VPNname
fi
When I run this script from cli directly, it works and starts ppp but when I run the same through cronjob (for root user), it doesn't work.
I tried the below and didn't work
*/1 * * * * bash /root/vpn-check.sh > /root/cronlog.txt 2>&1
I tried the below and didn't work
*/1 * * * * /root/vpn-check.sh > /root/cronlog.txt 2>&1
Finally, I tried:
*/1 * * * * /usr/sbin/pppd call VPNname> /root/cronlog.txt 2>&1
Can't figure out what could be wrong.
I still don't understand why some scripts work and don't work from cron when it is being called as the correct user according to the logs.
The only solution I found is to run:
crontab -e
and add the following lines to the top (even though I am calling the pppd daemon by the full path):
SHELL=/bin/sh
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
I fixed it. All this while I was running crontab -e
but for the user name to be added, it needs to be added to the system-wide cron file found under /etc/crontab
user that starts the job can only be added in the above mentioned system wide cron file.
You are missing the shebang from your shell script.
vpn-check.sh should look like:
#!/bin/bash
ping -c3 10.8.3.0 > pingreport
result=`grep "0 received" pingreport`
truncresult="`echo "$result" | sed 's/^\(.................................\).*$/\1/'`"
if [[ $truncresult == "3 packets transmitted, 0 received" ]]; then
pon VPNname
fi
See:
http://linuxconfig.org/bash-scripting-tutorial
What does the line "#!/bin/sh" mean in a UNIX shell script?
I was getting the same problem too.I used #dave's answer to figure it out. You just need to add the user name to the crontab, Add the next line to the end of /etc/crontab file:
*/1 * * * * root bash /root/vpn.sh
Replace the shell name of your own.
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.