ZTree.com  | ZEN  | About...  

 Index   Back

Do buffers mess with verification?   [Discuss]

By: Ron Metzger       
Date: Jun 14,2018 at 12:02
In Response to: Do buffers mess with verification? (John Leslie)

> > As Liviu pointed out above
> > (http://www.ztw3.com/forum/forum_entry.php?id=121665), the verification
> > switches built into the copy and xcopy commands don't necessarily work
> > because they could be comparing file caches, not the actual contents of
> > the disk.
> >
> > With the amount of memory available these days, and with caches built
> > into drives, what do you have to do to be sure you're really verifying?
> > Reboot and compare?
> That was my original thought too, but certainly in the case of Syncback
> Pro and a Qnap NAS I was getting some verification errors which led to me
> finding some SATA bus errors, which the NAS had in its logs but didn't
> feel the need to communicate to me...

So, the crux of the problem is verifying beyond the 'cache,' correct?

If the verify fails on your NAS when using Explorer (or other non-console file manager), does the NAS verify failure get reported back to the program making copy request (Explorer, Syncback Pro, or Qnap)?

My guess is that Syncback Pro or Qnap are initiating a File Compare independently of the copy process, Correct?

If that is not correct, consider using ZTree CLP /APIT instead of using ZTreeWin's native copy process. (Or if using /APIT, use ZTreeWin's native copy process.)

If switching the use of /APIT (use, non-use) does not change things, ZTreeWin's Alt-Compare would be the only practical solution.

Alternatively, check your NAS provider for a firmware update to accommodate the SATA drives you have. Ultimately, that may be the best solution -- Eliminate the failure in the first place.

Hope this is helpful.
Ron Metzger

Thread locked

Messages in this Thread

95,060 Postings in 11,983 Threads, 350 registered users, 33 users online (0 registered, 33 guests)
Index | Admin contact |   Forum Time: Aug 3, 2020 - 8:11 am EDT  |  Hits:32,787,000  (10,201 Today )
RSS Feed