Will removing a node cause data loss in NCache?

No. In clustered topologies like Partitioned-Replica, NCache triggers an automated State Transfer upon node removal, moving data partitions to the remaining nodes to maintain full data integrity.

Should I use Force Delete when scaling down in Azure?

It is recommended to leave 'Force Delete' unchecked. This allows the termination event to fire, ensuring licenses are not left in a consumed state.

How should I scale down a cluster for maximum stability?

When scaling down in cloud environments like Azure, it is best practice to reduce the number of instances one at a time.

Remove Cache Server Node

A pre-existing server node can be simply removed from the cache it is a part of, using the NCache Management Center and PowerShell, etc., as detailed below.

Using the NCache Management Center

Launch the NCache Management Center by browsing to http://localhost:8251 or <server-ip>:8251.
In the left navigation bar, click on Clustered Caches. This opens up a new page. It shows any existing local or clustered caches and additional details like Server and Server Platform.
Against the cache name, click on View Details.

Remove Server Node Web

This opens the detailed configuration page for the cache. The Server Nodes tab displays a list and status of the existing server nodes of the cache.
Choose the node to be removed. Click on the button. A success notification will be displayed.

Server Node Removed Web

Note

You might get prompted with a dialog box upon these changes, asking whether to reload or overwrite the cache config file.

The server node is removed from the Server Nodes list.

Using PowerShell

The Remove Node cmdlet enables the user to remove a particular node from the existing cache on a server or a specified node from the provided clustered cache. The following command removes node 20.200.20.39 from demoCache.

Remove-Node -CacheName demoCache -Server 20.200.20.39

The following command removes the specified server node from the cache named demoCache from the local server by gracefully stopping it.

Remove-Node -CacheName demoCache -Server 20.200.20.39 -GracefulStop

The following command removes the specified server node from the cache named demoCache using security credentials.

Remove-Node –CacheName demoCache –Server 20.200.20.39 -Credentials(Get-Credential john_smith)

Remove Server Nodes in Azure (Scale Cluster)

NCache provides you with the option to scale down your cluster. To manually scale down your NCache cluster, follow these steps within the Azure portal:

Important

When scaling down the cluster, it is recommended to reduce the number of instances one at a time to ensure cluster stability.

Navigate to your Resource Group, select your VMSS, and locate the Scaling option under the Availability + scale section in the left menu.
Choose Manual scale from the available scaling options.
Either enter the specific number of instances you require or use the slider bar to reach your desired server count as shown below:

Removing Specific Cache Instance

You can also remove a specific instance from your list of instances, for that you have to:

Navigate to your Virtual Machine Scale Set.
Select Instances from the left menu. This will open up a page listing the instances you have created.
Select the instance you want to delete from the list, here we are deleting the instance Test_0 as shown below.
In doing so, we recommend leaving the Force Delete checkbox unchecked.
Enabling this option prevents the Termination event from firing, which will result in your license remaining in a consumed state.

This will scale down the cluster and deleted instances will be automatically removed from all existing caches within the deployment.