rsync: "-c" option clarification

Kevin Korb kmk at
Thu Mar 23 19:49:53 UTC 2017

The -c option causes rsync to checksum EVERY file on both ends BEFORE
rsync does anything else.  It checksums files that are on only 1 end.
It checksums files that are different sizes.  It will not catch a
hardware problem preventing rsync from writing a file correctly.

On 03/23/2017 03:12 PM, steven banville via rsync wrote:
> Hi
> I am using "rsync" to send files from a source machine to a remote
> machine as one typically does.  I would like to clarify that the "-c"
> option will cause the checksum on the receiving end to be created by
> reading the already written file and NOT the data stream on the
> receiving end.  This would help in catching disk I/O errors if the
> checksum is done on the file on disk.
> I understand if the size and (or date?) don't match, the checksum is not
> needed on the receiving end.
> I may be missing something but it wasn't entirely clear to me that the
> checksum is done based on the file on disk.
> Thanks,
> -Steve

	Kevin Korb			Phone:    (407) 252-6853
	Systems Administrator		Internet:
	FutureQuest, Inc.		Kevin at  (work)
	Orlando, Florida		kmk at (personal)
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