ONTAP API error: "Could not create path, error = System.IO.IOException: The system cannot open the file."

Applies to

• SMB2.X/3.X
• ONTAP 9.2X
• Multiple files open

Issue

• Error from NetApp API: "NetAppRestAPIImpl->GetPathForProduct: Could not create path, error = System.IO.IOException: The system cannot open the file"
• Opening and closing files takes longer than expected
• sktraces logs show rt=379 (RESULT_ERROR_CIFS_SMB_FILE_LIMIT_EXCEEDED):

                ... NBLADE_Chk:  n0x80bdae: src/Protocols/Cifs/FrameWork/Connection.cpp:1148 rt=379

• "vserver cifs session show"  command shows 524287 open files on a single cifs connection. Example:

                Node: <Node_Name>

                Vserver: <Vserver_Name>

                Connection Session Open Idle Connection

                ID ID Workstation Windows User Files Time Count

                ---------- ------- ---------------- ---------------- --------- ------------ ---------------

                ...

                192.168.1.42 DOMAIN\User1 524287

                ...