Example Use Cases

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Some example operations that an application will use PAWS to accomplish are:

 

Discovering cluster nodes

Downloading and verifying that upgrade files are on each server

Managing backup jobs

Restarting server nodes

Performing upgrades

 

This example use case illustrates how to use PAWS to perform some of these tasks.  You can find details about each of the services in the PAWS API Reference.

 

Use Case: Managing a Cluster Upgrade

 

To manage a cluster upgrade using PAWS, you need to perform the following steps.

 

1.Identify nodes in the cluster

2.Validate installed versions of Unified CM

3.Verify upgrade validity

4.Download and prepare upgrade file on server

5.Start the upgrade

6.Check status of upgrade

7.Switch to upgraded software version

 

The following diagram illustrates how you would accomplish these steps using the PAWS services.

 

upgrade-cluster

1. Identify nodes in the cluster

The ClusterNodeService can be used to identify the nodes in the cluster. The getClusterNodes interface returns details about all of the nodes in cluster, and the getMyClusterNode interface returns details about the node that receives the request.

 
Each node in the cluster will have a ClusterNode element in the response.  The ClusterNode element will include the IP address of the node, the alpha-numeric alias for the node, the URL of the node's host server, and if the node is a primary or secondary type node.

 

2. Validate installed versions of Unified CM

The VersionInformationService provides two interfaces: getActiveVersion, getInactiveVersion.  The response for this service returns the version (for example: 8.6.0.98000-9005).  The version element will be empty, if there is not an inactive version.

 

3. Verify upgrade validity

The UpgradeFilterService provides the upgradeFilter interface.  This service returns a response that either contains a list of the files from the provided list that are valid upgrades, or returns a message indicating that none of the files in the request are present.

 

A successful response includes the valid filename(s).  For example,  UCSInstall_UCOS_8.6.0.96000-9007.iso.

 

4. Download and prepare upgrade file on server

The PrepareRemoteUpgradeService provides the prepareRemoteUpgrade interface.  This service downloads and prepares an upgrade or Cisco Option Package (COP) file for installation.

 

The response will indicate success or failure.

 

You can use the UpgradeStageService to check the status of the prepareRemoteUpgrade request.

 

5. Start the upgrade

The StartUpgradeService provides the startUpgrade interface which is use to begin the upgrade. The request must include a 'Session ID' which is used to ensure that only one upgrade process is being managed at a time.

 

The response will indicate success or failure.

 

6. Check status of upgrade

The UpgradeStageService service provides the getUpgradeStage interface.  The service returns the current overall upgrade or Cisco Option Package (COP) file installation stage.

 

Some of the stages that may be returned are: Cancelled, Completed, Configuring, Downloading, Error, Installing.

 

7. Switch to upgraded software version

The SwitchVersionService provides the switchVersions interface.  This service activates and boots the inactive partition. You can use the SwitchVersionStatusService to check the status of switchVersions.

 

There is no response from this service when it completes, because the server restarts.

 

A failure response provides an indication of why the request failed.