Network and Storage Protocols

[filer:cifs.smb2.client.signing:error]: Connection to server:\\DC failed due to mismatch


Hi @ all,


we are currently migrating our DCs from w2k8 to Windows Server 2019. We have installed 2 new servers and the corresponding roles and upgraded them to DCs. They should take over the IP addresses of the two existing w2k8 DCs or this is already the case with one of them.
Now the Netapp (Version 8.2.4P5 7-Mode) shows every now and then (or with cifs testdc) for the DC that has taken over the IP the message:
[Filer:cifs.smb2.client.signing:error]: Connection to server:\\DC02 failed due to mismatch in signature.
I have searched a lot but have not found a solution yet.
Cifs signing is disabled:
options cifs.smb
cifs.smb2.client.enable on
cifs.smb2.enable on
cifs.smb2.signing.max_threads 3
cifs.smb2.signing.multiprocessing default
cifs.smb2.signing.required off
cifs.smb2_1.branch_cache.enable off
cifs.smb2_1.branch_cache.hash_time_out 3600 (value might be overwritten in takeover)
cifs.smbx_signing_required off


Is this a serious problem? Does anyone have an idea or solution?

Best regards André



Hi there,


Can you confirm you're running Data ONTAP 8.2.5P5? This is the only version which will work with Windows Server 2019


Then run "options cifs.smb2.signing.required on" and "options cifs.smbx.signing.required on"


Hope this helps!