Rsync completed successfully, but files are not identical

[Matthias Schniedermeyer]

On 16.08.2009 13:17, Mark, Oren wrote:
> BTW - Could it be because 2 rsync were running in parallel? 

You mean 2 rsyncs syncing the same source to the same destination?

Can't really tell what that would do, i'm not familiar with the exact MO 
of rsync and there are commandline options that would make huge 
differences in this scenario.


> Thanks,
> Oren Mark
> 
> -----Original Message-----
> From: Mark, Oren 
> Sent: Sunday, August 16, 2009 1:01 PM
> To: Matthias Schniedermeyer
> Cc: rsync at lists.samba.org; Mark, Oren
> Subject: RE: Rsync completed successfully, but files are not identical
> 
> The only thing I can think about is backup program that change the atime after the backup and indeed, there was backup running at the time of this rsync.
> But I am still trying to picture the scenario and I can't get it, since the file attributes are the same and only the data is not identical.  
> 
> You mean that the file was change while the access time value was update by the backup and then it was restored backup by the backup program, so it doesn't have the correct atime and mtime? 
> 
> Thanks,
> Oren Mark
> 
> -----Original Message-----
> From: Matthias Schniedermeyer [mailto:ms at citd.de] 
> Sent: Sunday, August 16, 2009 12:20 PM
> To: Mark, Oren
> Cc: rsync at lists.samba.org
> Subject: Re: Rsync completed successfully, but files are not identical
> 
> On 16.08.2009 11:38, Mark, Oren wrote:
> > Hi All,
> > 
> > I came into a strange issue running rsync on directory with ~500,000 files.
> > Some of the file, although with same time stamps and size on source and destination, were different on the destination.
> > The destination is just a mirrored area, and the data written to it, is just the one that comes through rsync.
> > Needless to mentioned, that when I remove files and synced them again it works, or when I did the sync with checksum.
> > 
> > Due to the large number of files, running it with checksum is very bad options for me.
> > 
> > I have few questions:
> > 
> > 1)      Any idea how come a replicated area, has files with same time stamp and size, but file is different than the source?
> > 2)      Is there a way for rsync to verify, that each transferred size is identical as the source, after the file was transferred?
> 
> My first question would be if i have a program on the source side that 
> "tampers" with files and then resets the atime/mtime, as long as the 
> size stays the same it's the same file for rsync.
> 
> And i faintly remember reading about an issue with mtime and mmap 
> writing files. I don't remember the details, but i guess if there was an 
> issue it is remedied in recent kernels.
> 
> 
> IOW i'm quite sure the culprit isn't rsync.
> 
> 
> 
> Bis denn
> 
> -- 
> Real Programmers consider "what you see is what you get" to be just as 
> bad a concept in Text Editors as it is in women. No, the Real Programmer
> wants a "you asked for it, you got it" text editor -- complicated, 
> cryptic, powerful, unforgiving, dangerous.
> 
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Bis denn

-- 
Real Programmers consider "what you see is what you get" to be just as 
bad a concept in Text Editors as it is in women. No, the Real Programmer
wants a "you asked for it, you got it" text editor -- complicated, 
cryptic, powerful, unforgiving, dangerous.