If an administrator (e.g. a Client with access to the DirectoryAdmin Role) registers a LocalDiscoveryServer with the GDS, then the GDS periodically adds Servers to a list for review by calling FindServersOnNetwork or FindServers on the LDS. Figure 11 shows the relationship between a GDS and the LDS-ME or LDS.
The GDS shall not make Servers discovered in this manner available via QueryApplications for FindApplications before an administrator has approved the Server on a case by case basis or via automated rules. Note that auto-population can result in conflicts where multiple Servers have the same ApplicationUri due to a configuration error. A GDS should keep track of these conflicts so an administrator can review and resolve them.
Figure 11 – The Relationship Between GDS and other components
The steps shown in Figure 11 are:
1 |
The Server calls RegisterServer2 on the LDS running on the same computer. |
2 |
The administrator registers LDS-ME installations with the GDS. |
3 |
The GDS calls FindServersOnNetwork on the LDS-ME to find all applications on the same MulticastSubnet. |
4 |
The GDS creates a record for each application returned by the LDS-ME. These records shall be approved before they are made available to Clients of the GDS. This approval can be obtained from an DiscoveryAdmin. |
5 |
The Client calls QueryApplications Method on the GDS to discover applications. |
The Information Model used for registration and discovery is shown in 6.6.1. Any Client shall be able to call the QueryApplications Method to find applications known to GDS. The complete definitions for each of the types used are described in 7.8.
Once a Server is registered with the GDS the record does not dissappear if the Server goes offline. If a Server is permentently taken offline the administrator needs to manually remove the registration.The interactions described above apply to Servers automatically discovered via an LDS. Servers can also be discovered by another application and registered automatically with the GDS provided the other application has the necessary administrative rights on the GDS.