Max CIFS Connection Exceeded

Question

While performing health checks on the cluster through UnifiedMgr, I saw the following error for the HA cluster we have on an AFF A300: Max CIFS Connection Exceeded.

Is there a way to check where exactly the CIFS connection was exceeded and should I be worried about this notification? To the best of my knowledge, there were no times that users reported files not opening due to this connection limit being exceeded.

Ontapforrum · Accepted Answer

I wouldn't be worried unless it has been flagging consistently. This incident may have happend at some point during established CIFS connections, but if the error does not repeat itself, no action is needed.

You haven't mentioned ONTAP & SMB version and also if the CIFS/SMB is used as regular shares or is it also serving to any application, hence I suggest checking 'event log show' command output on the Cluster to see if there is more info around this which might help trace the root cause/client/application.

Following related kbs are just for reference:

For SM1, it is called 'cifs.max_mp':
https://kb.netapp.com/onprem/ontap/da/NAS/CIFS_Max_Multiplex_and_how_to_increase_maximum_number_of_simultaneous_outstanding_Windows_client

For SMB2 or later, it is called 'credits':
https://kb.netapp.com/onprem/ontap/da/NAS/How_ONTAP_implements_SMB_crediting