The offline (or in-place) upgrade process requires you to shutdown all the applications using the cluster, and the entire Membase Server or Couchbase Server cluster. With the cluster switched off, you can then perform the upgrade process on each of the nodes, and bring your cluster and application back up again.
It's important to ensure that your disk write queue ( Section 11.3, “Disk Write Queue” ) has been completely drained before shutting down the cluster service. This will ensure that all data has been persisted to disk and will be available after the upgrade. It is a best practice to turn off the application and allow the queue to drain prior to beginning the upgrade.
To upgrade an existing cluster using the offline method:
Turn off your application, so that no requests are going to your Membase Cluster. You can monitor the activity of your cluster by using the Administration Web Console.
With the application switched off, the cluster now needs to complete writing the information stored out to disk. This will ensure that when you cluster is restarted, all of your data remains available. You can do this by monitoring the Disk Write Queue within the Web Console. The disk write queue should reach zero (i.e. no data remaining to be written to disk).
On each node within the cluster:
Shutdown the Membase Server or Couchbase Server process.
On the node to be upgraded, stop the Couchbase Server process. For guidance on specific platforms, see Section 3.2, “Startup and Shutdown of Couchbase Server” .
With Couchbase Server shutdown on the node, you can perform a standard node upgrade to the new version of Couchbase Server. See Section 2.3.3, “Node Upgrade Process” for details.
Couchbase Server should be started automatically on each node as you perform the upgrade.
As the cluster is warming up again, you can monitor the status of the warmup process to determine when you can switch on your application. See Section 11.2, “Monitoring startup (warmup)” .
Once the cluster has been started up again, you can re-enable your application on the upgraded cluster.