Forum Discussion
kurgan
Mar 22, 2019Copper Contributor
W10-1903 UNC path failing 0x80070043
I can no longer access network shares through unc paths \\server\share I get the 0x80070043 "Network name cannot be found" error. I suspect that this is related to the removal of Homegroups? but ...
- Jun 13, 2019
Hi everyone. We got access to the Dell KB and see the issue in Dell/EMCs 'Unity' CIFS implementation.
From the DELL EMC KB attached to thread (below), the Unity SMB Server implementation is failing on the "SMB2_NETNAME_CONTEXT" and "SMB2_COMPRESSION_CAPABILITIES" we added in 1903. These were changes designed to add some new capabilities to SMB; we make some variant of these at most OS releases. If an SMB/CIFS server doesn't recognize capabilities, it should ignore them, not fail. Otherwise Dell would have to update their SMB implementation every time we released a new SMB capability that didn't also include a protocol dialect revision (like "SMB 3.1.2"), forever and ever.
Error Messages in the Unity c4_safe_ktrace.log:
sade:SMB: 3:[nas_serverx] Unrecognized SMB2 negotiate context type 0003
sade:SMB: 3:[nas_serverx] Unrecognized SMB2 negotiate context type 0003SMB client sends the compression context before the netname context, so the server encounters the compression context first. The Unity server would probably encounter the same problem with the netname context. Instead of failing when their SMB Server version doesn't support more advanced capabilities, it should be ignoring those capabilities. This is what Windows and other 3rd party SMB products do.
kurgan thanks for opening this techcommunity item, I'm sorry I didn't see it until now.
Ned Pyle | Principal Program Manager, MS | @nerdpyle on twitter
dwatson
May 09, 2019Copper Contributor
Good news, everyone!
Dell/EMC has a work around for this issue. By setting the SMB Max Protocol version to 3.0.2 (down from 3.1.1) I am able to access shares again. Please start a Dell/EMC support ticket and quote SR 14282798.
Kudos to engineer Harsha Vardan for providing the work around!
- DarrenMillerMay 13, 2019Copper Contributor
dwatson Presumably this fix is for Unity?
We still have the same problem with FluidFS and Dell have told us it is Microsoft's problem.
Has anybody found a fix for FluidFS?
- DarrenMillerMay 13, 2019Copper Contributor
Just answering my own question - it looks like completely disabling SMBv3 on FluidFS is a workaround. Not great, but at least it gets things working again.
- itkpliMay 10, 2019Copper Contributor
dwatsonI got the same info yesterday as well from a local EMC representative who had looked at your SR and it's good that they have a workaround.
However there are quite a lot of improvements in 3.1.1 compared to 3.02.
More info: What’s new in SMB 3.1.1 in the Windows Server 2016 Technical Preview 2