Simultaneous rsyncs?

[Marc Sarrel]

Hi,

What would happen if two people ran rsync on the same set of source 
files to the same destination machine?  Do we need some sort of 
queuing or interlock mechanism to prevent simultaneous rsyncs?

We have a script that uses rsync to distribute files from our AFS 
space here to the local disks of about twenty-five machines around 
the US and Europe.  There are about ten or fifteen people here who 
update the source directory and run the distribution script.

So, someone might update the source directory while someone else is 
already doing a distribution.  That's actually not so bad, since when 
the first person then does a distribution, things will again be in 
sync.

More problematical is when two or more distributions overlap.  What 
would happen in that case?

It takes about twenty or thirty minutes to distribute the files to 
all the machines on our list.  So, it's possible that the two rsyncs 
would be working on the same destination machine at the same time.

If we don't need some sort of queue or interlock, then do we need to 
run a third rsync after the overlapping pair have finished to make 
sure that everything's OK?

Thanks,

Marc
-- 
Spitzer Space Telescope
Downlink Systems Engineer
+1 818 393-7786 (voice)
+1 818 393-6236 (fax)
Mail Stop: 264-767
mailto:Marc.A.Sarrel at jpl.nasa.gov

Pager:
+1 800 759-8888 PIN 5877194
mailto:5877194 at skymail.com
http://www.skytel.com/Paging/pageme.cgi?pin=5877194,1