I have this easy script for checking connection of specific interface with one condition.
If interface exists do nothing, if not dial VPN
#!/bin/bash
FOUND=`grep "tap0" /proc/net/dev`
if [ -n "$FOUND" ] ; then
echo yes
else
openvpn /home/pi/vpn/data/bezpasaka.opvn > /home/pi/vpn/errors.txt
fi
When I execute that it is working.
I also needed to add in into crontab so
*/1 * * * * /home/pi/vpn/checkvpn.sh
It supposed to work, I tried different bash with mkdir only and it was working fine.
Cron execute checkvpn.sh (i can see that in processes using :
ps ax | grep 'checkvpn.sh'
The problem I think is, that after cron execute checkvpn.sh it dials VPN and it gooooes all to the end until it cancelled whole connection because he can't hold the session probably. Atleast that what I though after checking errors.txt file
Have you any idea about any solution?
openvpn /home/pi/vpn/data/bezpasaka.opvn > /home/pi/vpn/errors.txt
where does openvpn located? when the cron get executed it does not normally loads PATH variables and hence does not know how to execute openvpn. You need to give full path of openvpn like /usr/bin/openvpn in order for this to work.
also please check whether openvpn requires tty or not
Related
I'm trying to run only one instance of my back up script as a cron job.
I know I can do it with a function that checks if the process is running:
if pgrep -x rclone >/dev/null
then
# rclone is still running, backup is not done yet, exit.
exit
else
# rclone is not running.
# start backup.
/path/to/rclone/script.sh
fi
But after some research, I found out flock should be used instead of looking for process ID, in crontab -e, in this case, run the script every 30 minutes:
*/30 * * * * /usr/bin/flock -n /var/lock/myjob.lock /path/to/rclone/script.sh
Running the command above requires sudo. Therefore, the script asks for sudo password, and never runs. (I ran the command above manually, that's how I found out).
How exactly do I use flock? Do I type a variable in my script that injects the sudo password when flock asks for it? (I know it's not secure, so there must be a different way to do this).
I tried to research this subject but couldn't find any good answers that explain how to use it properly.
Thank you.
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 [[ $truncresult == "3 packets transmitted, 0 received" ]]; then
/usr/sbin/pppd call home
fi
First of all, check if cron service is running. You know the first question of the IT helpdesk: "Is the PC plugged in?".
For me, this was happening because the cronjob was executing from /root directory but my shell script (a script to pull the latest code from GitHub and run the tests) were in a different directory. So, I had to edit my script to have a cd to my scripts folder. My debug steps were
Verified that my script run independent of cron job
Checked /var/log/cron to see if the cron jobs are running. Verified that the job is running at the intended time
Added an echo command to the script to log the start and end times to a file. Verified that those were getting logged but not the actual commands
Logged the result of pwd to the same file and saw that the commands were getting executed from /root
Tried adding a cd to my script directory as the first line in the script. When the cron job kicked off this time, the script got executed just like in step 1.
it was timezone in my case. I scheduled cron with my local time but server has different timezone and it does not run at all. so make sure your server has same time by date cmd
first run command env > env.tmp
then run cat env.tmp
copy PATH=.................. Full line and paste into crontab -e, line before your cronjobs.
try this
/home/your site folder name/public_html/gistfile1.sh
set cron path like above
I'm trying to get a script to run at startup, but does nothing if I've connected to my Raspberry Pi via SSH.
So far I've got the crontab to automatically run the script checkssh.sh via #reboot sleep 30 && sudo bash ./checkssh.sh and './checkssh.sh' contains this:
#!/bin/bash
if [ -n "$SSH_CLIENT" ] || [ -n "$SSH_TTY" ]; then
echo "SSH CONNECTED"
else
./autobackup.sh
fi
Running checkssh.sh from an SSH terminal returns 'SSH CONNECTED' which is expected, and letting it run automatically from the crontab at reboot when SSH isn't connected works correctly. However, when it runs at boot and I connect via SSH as soon as it's available, it still runs the script. I'm not sure where this is going wrong.
I need it to run automatically and if there's no SSH connection run autobackup.sh , but if there is an SSH connection, not to run anything. The device I use for the SSH connection may vary & the network used may also vary, so a script that relies on specific IP's isn't ideal.
Thanks for any help :)
Those environment variables (SSH_CLIENT and SSH_TTY) are only set in the environment of an SSH session. You cannot check them from another process and expect them to fulfill your goals here.
Instead, run the program finger. This is the standard way to see who is logged in.
Probably you need to add some delay before running your script to allow for the SSH service to come up. If cron service comes up before the sshd does, you will have a failure. Try:
#reboot sleep 60 && bash ./checkssh.sh
Also I would substitute the '.' with the full script path.In one scenario I had to add as many as 120 seconds to get the #reboot crontab to work right. But ssh should not need as much. I guess you can trim 60 seconds according to your needs after you get it working.
I have a web server (odin) and a backup server (jofur). On jofur, I can run the following code to rsync my web directories (via key authentication) from odin to jofur:
rsync -avz -e ssh backups#odin.mydomain.net:/home/backups /home/myuser/odin
If I enter this into the command line, everything rsyncs perfectly:
myuser#jofur:~$ rsync -avz -e ssh backups#odin.mydomain.net:/home/backups /home/myuser/odin
receiving incremental file list
sent 23 bytes received 1921 bytes 1296.00 bytes/sec
total size is 349557271 speedup is 179813.41
I want this to run every morning, so I edited my crontab to read this:
0 4 * * * rsync -avz -e ssh backups#odin.mydomain.net:/home/backups /home/myuser/odin
This doesn't work. The following message is deposited in /var/mail/myuser:
Could not create directory '/home/myuser/.ssh'.
Host key verification failed.
rsync: connection unexpectedly closed (0 bytes received so far) [Receiver]
rsync error: unexplained error (code 255) at io.c(605) [Receiver=3.0.9]
I'm not sure what this error means. I'm wary of futzing blindly with permissions because I don't want to leave any backdoors open. Any suggestions?
Its hard to tell whether cron is using the wrong rsync binary or whether rsync requires some variable which is not being set in cron. Please set the stdout/stderr as shown below and pass on the output of the log file
Also, try doing a "which rsync" from the command line ; this will tell you which rsync you are using from the command line.
0 4 * * * rsync -avz -e ssh backups#odin.mydomain.net:/home/backups /home/myuser/odin > /tmp/cron_output.log 2>&1
EDIT :
Can you create a shell script called SOME_DIR/cron_job_rsync.sh which contains the following. Make sure you set the execute bit.
#!/bin/sh
/usr/sbin/rsync -avz -e ssh backups#odin.mydomain.net:/home/backups /home/myuser/odin
And modify the cronjob as shown below
0 4 * * * SOME_DIR/cron_job_rsync.sh >/tmp/cron_output.log 2>&1
I had a similar issue. Mine was the HOME directory was encrypted.
If your user is logged, it works the known_hosts.
But when it's a cron, the cron uses the right user BUT it does not have access to your $HOME/~/.ssh directory because is encrypted :-(
i got the same error just like you.
I finally found user home directory is an 'mount point', when logged in, it changed.
You can use the shell command 'mount' to check if you have the same way to use home directory.
So, i logged in and 'cd /', then do
```
cp -ar ${HOME}/.ssh /tmp/
sudo umount ${HOME}
mv /tmp/.ssh ${HOME}
```
There is may failed, because you need to check the ${HOME} if you have the right to write, if not, try sudo or add writable to ${HOME}.
After that, every thing being fine.
Please follow the below steps to avoid the error
http://umasarath52.blogspot.in/2013/09/solved-rsync-not-executing-via-cron.html
I resolved this issue by communicating with the administrators for my server. Here is what they told me:
For advanced security and performance, we use 1H (Hive) which
utilizes a chrooted environment for users. Libraries and binaries
should be copied to the chrooted environment to make them accessible.
They sent me a follow up email telling me that the "Relevent" packages have been installed. At that point, the problem was resolved. Unfortunately, I didn't get any additional information from them. The host was Arvixe, but I'm guessing that anyone using 1H (Hive) will encounter a similar problem. Hopefully this answer will be helpful.
Use the rrsync script together with a dedicated ssh key as follows:
REMOTE server
mkdir ~/bin
gunzip /usr/share/doc/rsync/scripts/rrsync.gz -c > ~/bin/rrsync
chmod +x ~/bin/rrsync
LOCAL computer
ssh-keygen -f ~/.ssh/id_remote_backup -C "Automated remote backup" #NO passphrase
scp ~/.ssh/id_remote_backup.pub devel#10.10.10.83:/home/devel/.ssh
REMOTE computer
cat id_remote_backup.pub >> authorized_keys
Prepend to the newly added line the following
command="$HOME/bin/rrsync -ro ~/backups/",no-agent-forwarding,no-port-forwarding,no-pty,no-user-rc,no-X11-forwarding
So that the result looks like
command="$HOME/bin/rrsync -ro ~/backups/",no-agent-forwarding,no-port-forwarding,no-pty,no-user-rc,no-X11-forwarding ssh-rsa AAA...vp Automated remote backup
LOCAL
Put in your crontab the following script with x permission:
#!/bin/sh
echo ""
echo ""
echo "CRON:" `date`
set -xv
rsync -e "ssh -i $HOME/.ssh/id_remote_backup" -avzP devel#10.10.10.83:/ /home/user/servidor
Source: http://www.guyrutenberg.com/2014/01/14/restricting-ssh-access-to-rsync/
I did several steps to make it work.
Check your paths. For every command you'll use check which [command] and use that full path for the crontab
Open crontab as the user you want to run it with so it has access to that users ssh-key
Add (remember to user which) ssh-agent && [your ssh-command] so it can connect over ssh.
When authentication still fails at this point. Try to generate a passwordless ssh-key. This way you can skip the password prompting.
For debugging it is useful to add -vvv to the ssh command in rsync. It makes it clear what goes wrong.
Using the correct keyring solved the issue for me. Add the following line to your crontab:
SSH_AUTH_SOCK=/run/user/1000/keyring/ssh
In total, your crontab (edited by calling crontab -e from your terminal) should now look as follows:
SSH_AUTH_SOCK=/run/user/1000/keyring/ssh
0 4 * * * rsync -avz backups#odin.mydomain.net:/home/backups /home/myuser/odin
Background: It turns out that some Linux distributions use a keyring to protect your public-private key pair - so the key pair is password-protected without ever noticing you. Consequently, rsync is not able to open your ssh key for authentication.
Note that I also omitted the -e ssh; I think it is not necessary here.
Further Troubleshooting: rsync does not provide a lot of debugging output. What helped me identify the problem was to put a dummy scp command, which is much more verbose, in my crontab. A crontab entry for troubleshooting may look something like:
* * * * * scp -v backups#odin.mydomain.net:/home/backups/dummy.txt /home/myuser/odin/dummy.txt >> /home/myuser/odin/dummy.txt.log 2>&1
The above command will run every minute (great for developing) and it will copy a file /home/backups/dummy.txt to your local machine. All logs (stdout and stderr) are written to to /home/myuser/odin/dummy.txt.log. Inspect these logs to see where the error precisely comes from.
Reference: The troubleshooting explained above lead me to the solution: https://unix.stackexchange.com/a/332353/395749
I have a linux shell script that when run from command line works perfectly but when scheduled to run via crontab, it does not give desired results.
The script is quite simple, it checks to see if mysql-proxy is running or not by checking if its pid is found using the pidof command. If found to be off, it attempts to start the proxy.
# Check if mysql proxy is off
# if found off, attempt to start it
if pidof mysql-proxy
then
echo "Proxy running."
else
echo "Proxy off ... attempting to restart"
/usr/local/mysql-proxy/bin/mysql-proxy -P 172.20.10.196:3306 --daemon --proxy-backend-addresses=172.20.10.194 --proxy-backend-addresses=172.20.10.195
if pidof mysql-proxy
then
echo "Proxy started"
else
echo "Proxy restar failed"
fi
fi
echo "==============================================="
The script is saved in a file check-sql-proxy.sh and has permissions set to 777. When I run the script from command line (sh check-sql-proxy.sh) it gives the desired output.
4066
Proxy running.
===============================================
The script is also scheduled to run every 5 minutes in crontab as
*/5 * * * * bash /root/auto-restart-mysql-proxy.sh > /dev/sql-proxy-restart-log.log
However, when I see the sql-proxy-restart-log.log file it contains the output:
Proxy off ... attempting to restart
Proxy restar failed
===============================================
It seems that pidof command fails to return the pid of the running application which brings the flow of script in else condition.
I am unable to figure out how to resolve this since when I run the script manually, it works fine.
Can anyone help what I am missing with regards to permissions or settings?
Thanks in advance.
Mudasser
Check that the shell is what you think it is (usually /bin/sh, not bash)
Also check that PATH environment variable. Usually, for cron jobs it is a good practice to fully qualify all paths to binaries, e.g.
#!/bin/bash
# Check if mysql proxy is off
# if found off, attempt to start it
if /bin/pidof mysql-proxy
etc.
Try pidof /usr/local/mysql-proxy/bin/mysql-proxy (full path to executable)
In common, try use the same command name as was used to start the instance of mysql-proxy.
The problem seems that crontab environment don't have the same environment as you.
You have 2 simple & proper solutions :
In the first lines of crontab :
PATH=/foo:/bar:/qux
SHELL=/bin/bash
or
source ~/.bashrc
in your scripts.