Comment on Prevent rsync cronjob to run multiple times via cronjob on Linux by hip0d.
Here is another life time example with flock:
*/5 * * * * /usr/bin/rsync –delete -a source_server:/source/path/ /dst/path/
Example using flock:
*/5 * * * * flock -xn /tmp/example.lock -c '/usr/bin/rsync –delete -a source_server:/source/path/ /dst/path/'
hip0d Also Commented
Prevent rsync cronjob to run multiple times via cronjob on Linux
Another way I just red on a blog is as follows:
$ crontab -l
* * * * * /path/to/cron.sh
The command above will, just as the first example, execute our PHP script every minute through a bash script. To prevent it from overlapping, it can also be changed to this.
$ crontab -l
* * * * * /usr/bin/pgrep -f /path/to/cron.sh > /dev/null 2> /dev/null || /path/to/cron.sh
The pgrep command will return false if it does not find a running process matching the first argument, /path/to/cron.sh. If it returns false, it'll process the second part of the OR comparison (the double vertical line, ||). If the running process was found, pgrep will return the Process ID (PID) and Bash will not continue to the second part of the OR statement since the first already returned true.
The trick here is to use very unique scriptnames. If the name is too generic (such as "cron.sh"), pgrep may return Process IDs from other running cron jobs and not execute the cron you wanted.
Recent Comments by hip0d
От архива: Христовата любов побеждава дори смъртта, твърдеше приживе патриарх Неофит
Българският Патриарх Неофит в Москва на 8 Март 2016 г. ЧАСТ 2
Christ is Risen Eastern Orthodox Resurrection Paschal Greeting in Different Languages
Hi Stan,
I guess you cannot read the writtings on the icon as it is in cyrillic.
This is not Saint Mary and Saint Peter but Adam and Eve written in cyrillic on top of the icon.
Actually in orthodoxy it is a requirement for the depicted personalities, especially saints to have
written on the names of the saint and have the Halo. If you look closely at the picture you will notice
the two Adam and Eve are missing a Halo. The only person with a Halo in the icon is Saint John the Baptist.
Best Regards
Georgi
Install and configure rkhunter for improved security on a PCI DSS Linux / BSD servers with no access to Internet
–rwo, –report-warnings-only
This option causes only warning messages to be displayed. This can be useful when rkhunter is run via cron. Other options may
be used to force other items of information to be displayed.
–sk, –skip-keypress
When the –check command option is used, after certain sections of tests, the user will be prompted to press the return key
in order to continue. This option disables that feature, and rkhunter will run until all the tests have completed.
Install and configure rkhunter for improved security on a PCI DSS Linux / BSD servers with no access to Internet
As rkhunter check, can be pretty annoying and ask you to press keypresses multiple times and spit you a lot of unnecessery data a very good useful option arguments are:
–rwo and –sk
# rkhunter -c –rwo –sk
Warning: The SSH and rkhunter configuration options should be the same:
SSH configuration option 'PermitRootLogin': yes
Rkhunter configuration option 'ALLOW_SSH_ROOT_USER': no
