In any production environment, there are situations that require an administrator to stop production services for a while to perform certain operations on production nodes. This may be planned nodes servicing, their planned stops, or planned power outage, etc. After turning on the nodes and resuming their production operation, it is beneficial to have fully-synchronized data on all nodes in order to avoid the long-lasting synchronization process that can take a considerable amount of time in most production environments.
The enabling of the Maintenance mode in StarWind Management Console before planned shutdowns saves the time required for data synchronization between the nodes after exiting the Maintenance mode and simplifies the process of making any changes in highly-available production environments.
To simplify the production startup after the scheduled service interruption, just turn on the Maintenance mode before performing various actions (shutdown, reboot, etc.) on the nodes. Even if nodes are turned off incorrectly after entering the Maintenance mode, all data will be safe. After finishing the operations on the nodes, just exit the Maintenance mode. As soon as this has been done, production can be launched without any need to wait for either fast or full synchronization. The only thing that should be checked is connectivity between the devices under maintenance.
When a device enters the Maintenance mode, it should contain a fully-synchronized data on all HA nodes. The Maintenance mode for the selected device will be enabled/disabled on all nodes simultaneously. When an HA device is in the Maintenance mode, connection to this HA device is blocked on any node containing it to ensure the integrity of data till the Maintenance mode is off. As a result, the synchronization before starting the HA operation is avoided, as data on all nodes is completely identical to what had been there before entering the Maintenance mode.
To enable Maintenance Mode, perform one of the following actions:
- Right-click the device and select Enter Maintenance Mode from the shortcut menu
- Select a StarWind device and click the Enter Maintenance Mode button on the toolbar.
NOTE: Only the HA device selected will enter into Maintenance mode. In case you need to reboot or shut down the node, the Maintenance mode must be enabled on all the HA devices present on the node. Make sure that you have shut down production VMs that use the storage before devices enter the Maintenance mode. The Maintenance mode should also be enabled in a hypervisor environment. The StarWind Maintenance mode for the selected device will be enabled/disabled on all nodes simultaneously.
Click Continue to enable the Maintenance mode.
Click Continue to enable the Maintenance mode.
The Maintenance mode status appears in the StarWind Console.
To exit the Maintenance Mode, perform one of the following actions:
- Right-click the device and select Exit Maintenance Mode from the shortcut menu
- Select a StarWind device and click the Exit Maintenance Mode button on the toolbar.
Exiting the Maintenance mode allows the nodes to start working in the normal operation mode without either full or fast synchronization.