Command options to limit excessive Windows client resource consumption


Options to the vserver cifs options modify command enable you to control resource consumption for Windows clients. This can be helpful if any clients are outside normal bounds of resource consumption, for example, if there are unusually high numbers of files open, sessions open, or change notify requests.

The following options to the vserver cifs options modify command have been added to control Windows client resource consumption. If the maximum value for any of these options is exceeded, the request is denied and an EMS message is sent. An EMS warning message is also sent when 80 percent of the configured limit for these options is reached.

  • -max-opens-same-file-per-tree

    Maximum number of opens on the same file per CIFS tree

  • -max-same-user-sessions-per-connection

    Maximum number of sessions opened by the same user per connection

  • -max-same-tree-connect-per-session

    Maximum number of tree connects on the same share per session

  • -max-watches-set-per-tree

    Maximum number of watches (also known as change notifies) established per tree

See the man pages for the default limits and to display the current configuration.

Beginning in ONTAP 9.4, servers running SMB version 2 or later can limit the number of outstanding requests (SMB credits) that the client can send to the server on a SMB connection. The management of SMB credits is initiated by the client and controlled by the server.

The maximum number of outstanding requests that can be granted on an SMB connection is controlled by the -max-credits option. The default value for this option is 128.