Maintenance Mode for Cache Management
NCache Maintenance Mode is a dedicated state for the Partition-Replica caching topology that enables administrators to carry out software patching, hardware upgrades, or server maintenance without any application downtime.
When performing server-side updates, shutting down a node has always triggered an automatic state transfer throughout the entire cluster, which has been known to increase CPU and network resource usage. NCache's maintenance mode addresses this issue by pausing state transfer when a node is temporarily stopped for maintenance. To learn more about maintenance mode, please refer to the NCache Architecture.
How to Stop Node for Maintenance
You can perform maintenance on your server node without triggering state transfer by stopping the server node. The following methods allow you to stop a server node for maintenance/cache management:
Important
You need to start your node within the timeframe of the maintenance mode, failing to do so will result in the state transfer being triggered after the maintenance time runs out.
Stop Node via NCache Management Center (GUI)
Launch the NCache Management Center by browsing to http://localhost:8251 or
<server-ip>:8251on Windows and Linux.In the left navigation bar, click on Clustered Caches. Next to the cache name, click on View Details.
This will open the detailed configuration page for the cache.
Under Server Nodes tab, check the box against the server node IP.
Click on "..." against the server IP and select Stop for Maintenance.
- The node status will change from Running to Stopped.
Important
No other node on the same clustered cache can be stopped during the maintenance mode. If you attempt to do so, it will give you an error saying "cluster is already under maintenance".
Stop Node via PowerShell/Command Line (CLI)
The IsStopForMaintenance/isstopformaintenance flag of the Stop Cache Command Line Tool stops a server node for maintenance.
The following command stops the node 20.200.20.39 of the cache demoClusteredCache for maintenance for a time of 30 minutes:
Stop-Cache -Name demoClusteredCache -Server 20.200.20.39 -IsStopForMaintenance -Timeout 30
How to Exit Maintenance Mode
You can exit the maintenance mode for a cluster by clicking on "..." against the cache and selecting Exit Maintenance Mode.
