@AlainTansi , Agree 100% it's not you. It's the docs misleading users... I'm afraid this thread is a re-run of this one regarding CA 😕 :
https://community.netapp.com/t5/ONTAP-Discussions/CIFS-NDO-and-Continuously-Available-Shares/td-p/140215
From here:
https://www.netapp.com/us/media/tr-4100.pdf - Nondisruptive Operations with SMB File SharesONTAP9.x
For CA:
"ONTAP 9 does not support persistent handles for use cases other than Microsoft Hyper-V over SMB and SQL Server over SMB".
For durable handles:
"When a LIF is migrated between nodes, client sessions become disconnected.SMB 1 is unable to prevent the lock state from being lost during these network outages, but SMB 2+clients,by using durable handles,can re establish disconnected sessions and maintain non disruptive operations. When an SMB 2 client opens a file and establishes a lock, a durable handle is created that records session details, the most important of which is the server that is associated with it. If the session is interrupted, the file remains open on the client, and the durable handle is used to reconnect the session."
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@ShahbazRiaz I don't have a working lab at the moment to test the NFS command for you. Maybe open a new thread on it if you don't find any existing ones...
I don't have other recommendations for NFS except of:
1. look for supportability in the IMT and any notes there (support.netapp.com/matrix),
2. get an upgrade advisor from ActiveIQ (https://mysupport.netapp.com/myautosupport/home.html),
3. if you wish to dig deep - look on open/fixed bugs between the two version you're upgrading to (https://mysupport.netapp.com/NOW/cgi-bin/bol/)
For SMB, there's a whole PDF TR on the second paragraph of this comment. But the main thing I can think of is to make sure your clients indeed not connected with SMB1 using the command
cifs sessions show -protocol-version SMB1