Network and Storage Protocols

"cifs.oplock.break.timeout" error



I hope that here is the right place to ask for help.

We use a Stretch MetroCluster built with FAS3210 release 8.1.1 7-Mode.

On this infrastructure we use two volumes one is NFS for virtual machines which works fine and the other is CIFS for many shares used in the Windows environment.

In the Windows environment (win2k8R2) we have different clients (WinXP, Win7): PCs, laptops, and Wyse terminals for Citrix environment.

I am fighting with the "cifs.oplock.break.timeout" error from one year ago, with technical support from NetApp, Citrix, Microsoft, suppliers, we applied a lot of patches for Windows environment and upgrades for NetApp storage, but we had no luck.

The most important for us is that we cannot use Excel files (MS Office2010) with the share workbook options enabled.

Daily few excel files are blocked/freeze and because of this we loss data, the users session is blocked and so on.

Any advise is very welcome.

Thank you,




Hi Florinel,

We had simular issues with an environment running 8.1.1, Citrix and Windows 2008 R2/Windows 7 systems.

After opening cases for this with NetApp, Citrix and Microsoft, they told us this has to do with the way CIFS/SMB is operating on the NetApp systems.

Connections to files were blocked, or not responding anymore.

Because we had folder redirections, sometimes systems were not responding anymore and gave us huge problems.

After upgrading tot 8.1.2. the problems dissapeared.

I have seen a lot of customers with file blockings, slow connections and not responding clients on 8.1.1. and SMB enabled.

There are some solutions, disabling SMB v2 is one, and not to use folder redirections.

But the only thing what I have seen working, is upgrading to 8.1.2.

Then also folder redirections and SMB v2.x will work.

I hope this will help you,



Hi Arco,

Thank you for info and sorry for the delayed answer (I believed that I will have an email about the news on this topic)

We already made two upgrades till version 8.1.1 and with all three versions we had the same issue...

- from Microsoft advise I have disabled SMB v2 and now we use v1

- from Citrix advise we have disabled CtxAltStr.sys driver

- from VMware advise I have changed the network configuration in order to use more physical NIC cards

- etc. etc...

Your suggestion sounds very hopeful and I will remember this!

Now I have a new open case to NetApp support.

PS: an old storage FAS2020, with version 7.4.3P1 works very well, but it is too small for the new environment we built last year

Thank you,