Application Center enables you to configure synchronization on the cluster-wide and individual member levels. As shown in Figure 6.7, the clustername Properties dialog box for the cluster lets you specify:
Figure 6.7 The RKStager Properties dialog box for configuring synchronization on a cluster
At the individual member level, you can use the membername Properties dialog box to take the member out of the synchronization loop by disabling synchronization for the member.
The synchronization exclusions feature provides increased flexibility by allowing you to synchronize part of a file tree by creating an exclusion list. This list is granular down to the individual file and file extension level.
This feature addresses two common scenarios:
You can create a synchronization exclusions list using by the Synchronization Properties dialog box (Figure 6.8), which is opened by right-clicking the Synchronizations node in the Application Center console tree.
NOTE
You have to create the exclusion list on the target rather than the source system. All files are transferred during synchronization, and exclusions are applied during the apply phase by the target. In cases where an exclusion list exists on both the source and target, the exclusions configured for the target are implemented.
This feature gives you the ability to exclude settings and content from replication on the basis of:
You can add as many items to the exclusions list as you want, provided that you use the preceding parameters for your exclusions.
NOTE
Exclusion by directory also includes specified subdirectories.
Figure 6.8 The Synchronization Properties dialog box for configuring synchronization exclusions
NOTE
Implemented via a File System driver attribute, the exclusion list can be created at the individual member level.
The exclusions list is a very useful tool; however, it should be used cautiously on any cluster because the list overrides all the default replication settings. There is the potential to completely disable all replication for critical settings and content on a cluster.
In addition to displaying real-time synchronization status information on the cluster and controller nodes' details pane (See sidebar). Application Center also provides a Synchronizations node in the console tree where you can view detailed synchronization and deployment information (Figure 6.9).
Replication phases during synchronization
During synchronization several status messages are displayed in the Synchronizations view that indicate which phase the synchronization is in. These phases and the major activities (Figure 6.4) for each are as follows:
- Initializing—The source server is starting a replication job.
- Scanning—The IHave lists are created on both the source and target(s), the lists are compared, and the target generates an Action list.
- Transferring—The Update list is sent to the target, and the required files are copied to a temporary directory on the target. The target notifies the source that it's ready to commit the session.
- Applying—The replicated files and configuration settings are written to the target.
Figure 6.9 The Synchronizations node and its details view
The upper part of the Synchronizations view displays summary information for a synchronization or deployment that's finished. (During synchronization, status indicators show the current stage of the synchronization: reading, transferring, or applying files. The following summary is provided:
The lower part of the Synchronizations view provides detailed information for a specific synchronization by using a General tab and an Events tab. The General tab displays:
The Events tab, illustrated in Figure 6.10, enables you to access event information that's generated for the synchronization. You can view All, Errors Only, Errors and Warnings, or a specific event by providing an event identifier as a filter.
Figure 6.10 Detailed error and warning event information for synchronization
Application Center's Synchronization and Deployment feature set provides a robust tool for quickly deploying complex business applications throughout your organization; these services also ensure that servers in both Web and COM+ application clusters remain synchronized with each other. Additionally, any activity related to synchronization and deployment is easy to monitor and audit.