Beginning with ONTAP 9.13, administrators can enable their NFSv4 servers to deny resources to NFSv4 clients when they have reached per client storepool resource limits. When clients consume too many NFSv4 storepool resources this can lead to other NFSv4 clients getting blocked due to unavailability of NFSv4 storepool resources.

Enabling this feature also allows customers to view the active storepool resource consumption by each client. This makes it easier to identify clients exhausting system resources, and makes it possible to impose per client resource limits.

View storepool resources consumed

The vserver nfs storepool show command shows the number of storepool resources consumed. A storepool is a pool of resources used by NFSv4 clients.

Step

As an administrator, run the vserver nfs storepool show command to display the storepool information of NFSv4 clients.

Example

This example displays the storepool information of NFSv4 clients.

cluster1::*> vserver nfs storepool show

Node: node1

Vserver: vs1

Data-Ip: 10.0.1.1

Client-Ip Protocol IsTrunked OwnerCount OpenCount DelegCount LockCount

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

10.0.2.1          nfs4.1     true    2 1 0 4

10.0.2.2          nfs4.2     true    2 1 0 4

2 entries were displayed.

Enable or disable storepool limit controls

Administrators can use the following commands to enable or disable storepool limit controls.

Step

As an administrator, perform one of the following actions:

If you want to… Enter the following command…

If you want to…	Enter the following command…
Enable storepool limit controls	`vserver nfs storepool config modify -limit-enforce enabled`
Disable storepool limit controls	`vserver nfs storepool config modify -limit-enforce disabled`

Enable storepool limit controls

vserver nfs storepool config modify -limit-enforce enabled

Disable storepool limit controls

vserver nfs storepool config modify -limit-enforce disabled

View a list of blocked clients

If the storepool limit is enabled, administrators can see which clients have been blocked upon reaching their per client resource threshold. Administrators can use the following command to see which clients have been marked as blocked clients.

Steps

Use the vserver nfs storepool blocked-client show command to display the NFSv4 blocked client list.

Remove a client from the blocked client list

Clients that reach their per client threshold will be disconnected and added to the block-client cache. Administrators can use the following command to remove the client from the block client cache. This will allow the client to connect to the ONTAP NFSV4 server.

Steps

Use the vserver nfs storepool blocked-client flush -client-ip <ip address> command to flush the storepool blocked client cache.
Use the vserver nfs storepool blocked-client show command to verify the client has been removed from the block client cache.

Example

This example displays a blocked client with the IP address "10.2.1.1" being flushed from all the nodes.

cluster1::*>vserver nfs storepool blocked-client flush -client-ip 10.2.1.1

cluster1::*>vserver nfs storepool blocked-client show

Node: node1

Client IP
----------
10.1.1.1

1 entries were displayed.