Month: October 2009

FIXED – NAS problem with Revit Central File access (oplocks) FIX

Luke Johnson

We use a Netgear ReadyNAS Duo as our fileserver. Recently we started to experience some annoying and disturbing error messages, such as:

  • Access to {path}{CentralFileName}-backupeperms.dat was denied
  • Encountered a hardware I/O error while accessing {path}{CentralFileName}-backuprequests.dat
  • An unknown error occurred while accessing {path}{CentralFileName}.rvt

This resulted in some loss of work and lots of annoyance.
I discussed the issue with our local reseller and they basically recommended I stop using the NAS and use a different share. But I didn’t want to do that! However, it did seem likely that the problem was with the NAS. I played around with some settings in the NAS setup…and I think I found the answer. It was to do with ‘oplocks’. I needed to disable the oplocks for the share, and the problem went away! How do you do it?

  1. In the Netgear ReadyNAS Duo ‘Frontview’ administration page, go to the ‘Shares’ page.
  2. Go to the ‘Share Options’ for the share you are using to store Revit Central Files.
  3. Scroll down the bottom to ‘Opportunistic Locking’ and disable the ‘Enable oplocks for this share’ tick box.

What are ‘oplocks’? According to the utility:
Opportunistic locking (oplocks) can enhance CIFS performance by allowing files residing on this ReadyNAS to be cached locally on the Windows client, eliminating network latency when files are repeatedly accessed.
This definition indicates that oplocks could certainly have caused this issue. Since disabling the option, we have experienced none of the aforementioned errors.
Have you experienced this problem? If so, I hope my solution helped you.
Also, it looks like I haven’t been the only one with an issue like this:
http://forums.novell.com/novell-product-support-forums/open-enterprise-server/oes-platform-independent/oes-client-windows/371285-revit-2009-64-bit-opportunistic-file-locking.html
http://www.mail-archive.com/samba@lists.samba.org/msg86717.html
http://forums.novell.com/novell-product-support-forums/open-enterprise-server/oes-netware/oes-nw-install-upgrade/369243-cifs-xp-pro-x64.html
http://community.riverbed.com/rvrb/board/message?board.id=24&thread.id=30
“Specific applications known to exhibit this behavior include Solidworks and AutoDesk Revit, as demonstrated by your experience.”

EDIT Associated issue may result in error such as:
This issue was with a user not being able to write to a particular file that Revit uses to maintain the state of the central file.
\pathdeltas.datpath
deltas.dat>