Re: RFE: Lockfile option for use in cronjobs
On Wed, 2 Apr 2008, Matt McCutchen wrote: On Mon, 2008-03-31 at 11:43 +0200, Dag Wieers wrote: Looking for an easy way to prevent a repetitive rsync to be running multiple times, I was wondering if it could be useful to have an option like: --pidfile /some/path/rsync-mirror-org.pid So that rsync can be run directly from cron without requiring a wrapper script to do pidfile handling. This way rsync on startup could check the pid-file, see if another rsync is using this pid, and bail out with an error if it is. Otherwise clean up the stale pidfile and continue. I think this would be very useful to instruct mirrors how to configure it, rather than providing some script that needs local customizations. I'm not convinced that a pidfile is better implemented in rsync than in a wrapper script, which could be distributed in support/ of the source tree. If you don't care about actually having the pid in the file, you could use the flock(1) utility, which executes a command while holding a flock(2) lock on a specified file: flock --nonblock /some/path/rsync-mirror-org.lock rsync ... If the process goes away, the lock will too, so no manual cleanup of stale locks is needed. The flock utility is great. I learn something new everyday :) Thanks a lot ! -- -- dag wieers, [EMAIL PROTECTED], http://dag.wieers.com/ -- [Any errors in spelling, tact or fact are transmission errors] -- To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html
Re: RFE: Lockfile option for use in cronjobs
On Thu, 10 Apr 2008, Dag Wieers wrote: On Wed, 2 Apr 2008, Matt McCutchen wrote: On Mon, 2008-03-31 at 11:43 +0200, Dag Wieers wrote: Looking for an easy way to prevent a repetitive rsync to be running multiple times, I was wondering if it could be useful to have an option like: --pidfile /some/path/rsync-mirror-org.pid So that rsync can be run directly from cron without requiring a wrapper script to do pidfile handling. This way rsync on startup could check the pid-file, see if another rsync is using this pid, and bail out with an error if it is. Otherwise clean up the stale pidfile and continue. I think this would be very useful to instruct mirrors how to configure it, rather than providing some script that needs local customizations. I'm not convinced that a pidfile is better implemented in rsync than in a wrapper script, which could be distributed in support/ of the source tree. If you don't care about actually having the pid in the file, you could use the flock(1) utility, which executes a command while holding a flock(2) lock on a specified file: flock --nonblock /some/path/rsync-mirror-org.lock rsync ... If the process goes away, the lock will too, so no manual cleanup of stale locks is needed. The flock utility is great. I learn something new everyday :) Just noticed that the flock utility is fairly recent (since util-linux 2.13) which means that on most systems you do not have it. For RHEL that means only available since RHEL5 :-( That could be one of the reasons to have it as part of rsync (to facilitate the distribution of a cron-job or simply make sure your mirrors are using best practices without too much complexity). -- -- dag wieers, [EMAIL PROTECTED], http://dag.wieers.com/ -- [Any errors in spelling, tact or fact are transmission errors] -- To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html
Re: RFE: Lockfile option for use in cronjobs
On Mon, 2008-03-31 at 11:43 +0200, Dag Wieers wrote: Looking for an easy way to prevent a repetitive rsync to be running multiple times, I was wondering if it could be useful to have an option like: --pidfile /some/path/rsync-mirror-org.pid So that rsync can be run directly from cron without requiring a wrapper script to do pidfile handling. This way rsync on startup could check the pid-file, see if another rsync is using this pid, and bail out with an error if it is. Otherwise clean up the stale pidfile and continue. I think this would be very useful to instruct mirrors how to configure it, rather than providing some script that needs local customizations. I'm not convinced that a pidfile is better implemented in rsync than in a wrapper script, which could be distributed in support/ of the source tree. If you don't care about actually having the pid in the file, you could use the flock(1) utility, which executes a command while holding a flock(2) lock on a specified file: flock --nonblock /some/path/rsync-mirror-org.lock rsync ... If the process goes away, the lock will too, so no manual cleanup of stale locks is needed. Matt -- To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html
