After you have created a hierarchy, you will want to extend that hierarchy to another server in the cluster. There are three possible scenarios to extend your resource instance from the template server to a target server. The first scenario is when you “Continue” from creating the resource into extending that resource to another server by clicking Next on the information dialog box displayed at the completion of the create. The second scenario is when you enter the Extend Resource Hierarchy task from the edit menu as shown below. The third scenario is when you right-click on an unextended hierarchy in either the left- or right-hand pane. Each scenario takes you through the same dialog boxes (with a few exceptions, which are clearly detailed below).
- If you are entering the Extend Wizard from the LifeKeeper GUI menu, select Edit, then Resource. From the drop-down menu, select Extend Resource Hierarchy. This will launch the Pre-Extend Resource Hierarchy Wizard.
- The first dialog box to appear will ask you to select the Template Server where your Oracle resource hierarchy is currently in service. It is important to remember that the Template Server you select now and the Tag to Extend that you select in the next dialog box represent an in service resource hierarchy. An error message will appear if you select a resource tag that is not in service on the template server you selected. The drop-down box in this dialog provides the names of all the servers in your cluster.
Note: If you are entering the Pre-Extend Resource Hierarchy task immediately following the creation of an Oracle resource hierarchy, this dialog box will not appear, since the wizard has already identified the template server in the create stage. This is also the case when you right-click on either the Oracle resource icon in the left hand pane or right-click on the Oracle resource box in the right hand pane the of the GUI window and choose Extend Resource Hierarchy.
It should be noted that if you click the Cancel button at any time during the sequence of extending your hierarchy, LifeKeeper will cancel the extension process to that particular server. However, if you have already extended the resource to another server, that instance will continue to be in effect until you specifically unextend it.
For example, let’s say you have created your resource on Server 1 and extended that resource to Server 2. In the middle of extending the same resource to Server 3, you change your mind and click on the Cancel button inside one of the dialog boxes. This will cancel only your action to extend the resource to Server 3, not the extension you created to Server 2. If you want to remove Server 2 from this hierarchy, you must unextend the resource from Server 2.
Click Next to proceed to the next dialog box.
- Select the Tag to Extend. This is the name of the Oracle instance you wish to extend from the template server to the target server. The wizard will list in the drop-down box all the resources that you have created on the template server, which you selected in the previous dialog box.
Note: Once again, if you are entering the Pre-Extend Resource Hierarchy task immediately following the creation of an Oracle resource hierarchy, this dialog box will not appear, since the wizard has already identified the tag name of your Oracle resource in the create stage. This is also the case when you right-click on either the Oracle resource icon in the left hand pane or on the Oracle resource box in the right hand pane the of the GUI window and choose Extend Resource Hierarchy.
Click Next to proceed to the next dialog box.
- Select the Target Server where you are extending your Oracle resource hierarchy. The drop-down box provides the names of the servers in your cluster that are not already in the selected hierarchy.
Click Next to proceed to the next dialog box.
- Select the Switchback Type. This dictates how the Oracle instance will be switched back to this server when it comes back into service after a failover to the backup server. You can choose either intelligent or automatic. Intelligent switchback requires administrative intervention to switch the instance back to the primary/original server. Automatic switchback means the switchback will occur as soon as the primary server comes back on line and reestablishes LifeKeeper communication paths.
The switchback type can be changed later, if desired, from the General tab of the Resource Properties dialog box.
Click Next to proceed to the next dialog box.
- Select or enter a Template Priority. This is the priority for the Oracle hierarchy on the server where it is currently in service. Any unused priority value from 1 to 999 is valid, where a lower number means a higher priority (1=highest). The extend process will reject any priority for this hierarchy that is already in use by another system. The default value is recommended. Note: This selection will appear only for the initial extend of the hierarchy.
- Select or enter the Target Priority. This is the priority for the new extended Oracle hierarchy relative to equivalent hierarchies on other servers. Any unused priority value from 1 to 999 is valid, indicating a server’s priority in the cascading failover sequence for the resource. A lower number means a higher priority (1=highest). Note that LifeKeeper assigns the number “1” to the server on which the hierarchy is created by default. The priorities need not be consecutive, but no two servers can have the same priority for a given resource.
Click Next.
- An information box will appear explaining that LifeKeeper has successfully checked your environment and that all the requirements for extending this Oracle resource have been met. If there were some requirements that had not been met, LifeKeeper would not allow you to select the Next button, and the Back button would be enabled.
If you click Back, you can make changes to your resource extension according to any error messages that may appear in the information box.
If you click Cancel now, you will need to come back and extend your Oracle resource hierarchy to another server at some other time to put it under LifeKeeper protection.
When you click Next, LifeKeeper will launch you into the Extend Resource Hierarchy configuration task.
- Once the Database Tag displays, click Extend.
- An information box will appear verifying that the extension is being performed.
Click Next Server if you want to extend the same Oracle resource instance to another server in your cluster. This will repeat the Extend Resource Hierarchy operation.
If you click Finish, another dialog box will appear confirming LifeKeeper has successfully extended your Oracle resource.
- Click Done to exit from the Extend Resources Hierarchy menu selection.
Note: Be sure to test the functionality of the new instance on both servers.
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