About Scaling an Oracle Java Cloud Service Node

You can scale a node in an Oracle Java Cloud Service instance to change its compute shape in response to changes in workload, or to add block storage to a node that is running out of storage. However, you cannot remove block storage from a node.

You must scale each node in a cluster individually. You cannot scale all nodes in a cluster in a single operation.

You can scale the Administration Server node and Managed Server nodes in a WebLogic Server cluster. You can also scale load balancer nodes (Not supported on Oracle Cloud at Customer). Oracle Java Cloud Service does not support scaling for nodes that make up the Coherence data tier.

Note:

You can scale a node only if a version of Oracle Java Cloud Service that supports scaling a node was used to create your service instance. If the version used to create your Oracle Java Cloud Service instance does not support scaling a node, you cannot scale a node.

Topics:

About Changing the Compute Shape of a Node

You can scale a node in an Oracle Java Cloud Service instance to change its compute shape. You must scale each node in a cluster individually. You cannot scale all nodes in a cluster in a single operation.

You can change the compute shape of a node to adjust capacity in response to changes in workload. The compute shape specifies the number of Oracle Compute Units (OCPUs) and amount of memory (RAM) that you want to allocate to the node.

Some services provide a set of compute shapes that are optimized for different use cases. Choose from a set of all-purpose and memory-intensive shapes. The larger the compute shape, the greater the processing power. For more information about the compute shapes and considerations for selecting the shape that is right for your environment, see:

Overview of the Compute Service in the Oracle Cloud Infrastructure Services documentation
About Shapes in Using Oracle Cloud Infrastructure Compute Classic

In general, Oracle recommends that the compute shapes of all nodes in a cluster are the same in order to optimize performance. To meet the demands of heavier workloads, scale up by choosing a larger compute shape. To save costs if the workload is lightened, scale down by choosing a smaller compute shape.

Note:

This section provides information to scale a compute shape of a JCS node while it is running. If the node is in the shutdown state, use the Resize REST API. See Resize a Service Instance.

What Happens When a Node is Being Scaled

Learn about the access, storage volumes, and others when you are scaling the node.

While a node is being scaled:

You can’t SSH to the node, and apps running on it can’t be accessed
You can’t run any admin operations on the instance
The storage volumes are detached, but remain intact

While Oracle Java Cloud Service is applying your changes, it puts the service instance into Maintenance mode, changes the state of the node to Configuring, and stops any servers running on the node. After applying your changes, Oracle Java Cloud Service starts any servers that should run on the node. At any time during the scaling process, you can check its status by clicking next to the instance name and the selecting View Activity. The Activity page will open and you can see the scale-in status in the activity table.

See Scale an Oracle Java Cloud Service Node.

What Happens After a Node is Scaled

Learn about the access, storage volumes, and others after you scale a node.

After the node is scaled:

The public IP address of the node won’t change
The node might get a different private IP address
The storage volumes are re-attached automatically

If you scale out a cluster in a service instance after scaling any of its nodes, the new node has the compute shape and the amount of storage with which the service instance was originally created. To ensure that all nodes in your cluster have the same shape and storage, you must scale the new node to match the other nodes in your cluster.

About Adding Block Storage to a Node

You can add block storage to a node in the virtual machine. When you add storage to a node that does not have any user-defined partition, a storage volume is created and attached to the node. But, if you subsequently add new storage volumes on the user-defined partition, the existing storage volume expands.

Note:

You cannot remove block storage from a node.

Caution:

Before adding storage, Oracle recommends that you back up the service instance to avoid the risk of data loss.

The new storage volume created by scaling remains attached and available to the node even when the service instance is restarted or is stopped and then started. Also, this storage volume exists until you delete the service instance, at which time the storage volume is also deleted.

Storage limits are described here:

Region Type	Storage Limits
Oracle Cloud Infrastructure Classic	You can perform up to 6 add-storage operations. Each time, you can add from 1 to 2048 GB.
Oracle Cloud Infrastructure	You can run up to 29 add-storage operations. In each operation, you can add capacity in 50-GB multiples up to a max of 2000 GB.