1. Migrate your on-premises Oracle WebLogic Server workloads to the cloud
  2. Scaling Managed Servers

Scaling Managed Servers

You can scale managed servers by changing the number of nodes or by changing the shape of the compute instances.

Add or Remove WebLogic Server Nodes

You can change the number of nodes (compute instances) in your Oracle WebLogic Server for Oracle Cloud Infrastructure stack to increase performance or to reduce costs. Add nodes to scale out, or remove nodes to scale in.

Note:

You cannot use this procedure to scale a domain that was created before June 29, 2020.

To scale the domain, edit the node count variable for the stack and then run an Apply job.

Oracle WebLogic Server for Oracle Cloud Infrastructure performs these tasks for a scaling operation:

  • Add or remove compute instances
  • Add or remove managed servers in the domain configuration (optional)
  • Add managed servers to the existing cluster in the domain configuration, if the domain is not running Oracle WebLogic Server Standard Edition (optional)
  • Update the backend set of the load balancer, if your stack includes a load balancer (optional)

If you customized your domain configuration after creating it (changing port numbers, changing server names, and so on), there is no guarantee that the domain modification part of the scaling job will succeed. You can disable this feature and perform these tasks manually after the scaling job completes.

  1. Sign in to the Oracle Cloud Infrastructure Console.
  2. Click the navigation menu, select Resource Manager, and then select Stacks.
  3. Select the Compartment that contains your stack.
  4. Click the name of your stack.
  5. Click Variables.
  6. Click Edit Variables.
  7. Edit WebLogic Server Node Count.
    If you increase the node count and modify the SSH Public Key, the key will be used for new compute instances only. The keys for existing compute instances remain unchanged.
  8. Optional: If you want Oracle WebLogic Server for Oracle Cloud Infrastructure to create compute instances but not update your domain configuration, select Do Not Update Domain Configuration For Scale Out.
  9. Click Next.
  10. Click Save Changes.
  11. Click Terraform Actions, and then click Apply.
  12. Enter a name for the job, and then click Apply.
  13. Periodically monitor the progress of the Apply job until it is finished.
  14. Click Outputs.
  15. Locate WebLogic_Instances, and verify the number of compute instances in the updated stack.

If you selected Do Not Update Domain Configuration For Scale Out, then you must manually update your domain configuration and add the managed servers. Use the WebLogic Server Administration Console or the WebLogic Server Scripting Tool (WLST).

If your domain is in a private subnet, the bastion compute instance is deleted and recreated. As a result, the bastion might have a different IP address.

Change the Shape of the Compute Instances

You can scale up the compute resources for your Oracle WebLogic Server for Oracle Cloud Infrastructure domain to increase performance, or you can scale down the compute resources to reduce costs.

Note:

Do not use Resource Manager to change the shape of the compute instances in your domain. You must use the Compute service. Using the resource manager to scale in and out after changing the shape will currently revert all nodes to the original shape, effectively destroying the domain. It is recommended to scale the number of nodes rather than the shape.

When you change the shape of a compute instance, you select a different processor, number of cores, amount of memory, network bandwidth, and maximum number of VNICs for the instance. The instance's public and private IP addresses, volume attachments, and VNIC attachments remain the same. For example, changing the shape of an instance from VM-Standard2.2 to VM-Standard2.4 doubles the capacity of the node from two OCPUs to four OCPUs, and also doubles the amount of memory allocated to the node.

The original shape of the compute instance determines which shapes you can select as a target for the new shape. You cannot modify the shape of an instance that uses a bare metal shape or certain virtual machine (VM) shapes.

Oracle recommends that you use the same shape for all compute instances that comprise a single WebLogic Server cluster. This allows traffic to be distributed uniformly across the cluster.

When you change a shape, the compute instance must be restarted. To avoid downtime and ensure your applications remain available to users, Oracle recommends that you create a cluster with multiple compute instances, and that you change the shape for one compute instance at a time.

When you change the shape of the first compute instance, the domain's administration server will be temporarily unavailable. However, your applications do not depend on the administration server and will not be affected.

  1. Sign in to the Oracle Cloud Infrastructure Console.
  2. From the navigation menu, click Compute, and then click Instances.
  3. Select the Compartment in which your domain was created.
  4. Click the name of the first compute instance for your domain.
    The instance has wls-0 appended to the name. For example: mydomain-wls-0
  5. Click Actions, and then select Change Shape.
  6. Select a new shape, and then click Change Shape.
  7. Repeat from step 2 for the remaining compute instances in your domain.