Example 2 — Two Application Servers, Same Subnet
As an iControl configuration grows, additional Application Servers can be added to handle the increased workload. Any TCP/IP devices associated with either Application Server should be on the same subnet.
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1. For the purpose of this example, Alpha is the only Application Server running the Lookup Service. Under actual conditions, you should have two Application Servers (per subnet) running the lookup service to provide redundancy.
2. The GSM is active on Alpha.
3. It is not necessary to type anything in Alpha’s Service and alarm discovery area. The discovery process will automatically result in all devices and services on Subnet A registering with Alpha’s Lookup Service.
IMPORTANT: System behavior |
If the Service and alarm discovery table of Application Servers is empty, client applications on the local Application Server can see services and alarms coming from the local GSM and all active GSMs on Application Servers within the subnet. |
4. In order to share the monitoring workload, the GSM is active on Bravo.
5. As mentioned above, the discovery process will result in all devices and services on Subnet A automatically registering with Alpha’s Lookup Service. So it would not ordinarily be necessary to type anything in Bravo’s Service and alarm discovery area. This is not true, however, when Bravo is accessed by a client PC from another subnet (see below).
6. When
iC Navigator (or any client application) is downloaded from Alpha by this PC, the application will perform a multicast discovery (
click HERE) within Subnet A, find the enabled Alpha Lookup Service, and then be able to see all devices and services registered on both Alpha and Bravo.
7. If this PC has access to Subnet A (e.g. via VPN), it can access Alpha’s iControl—Startup page from a Web browser, and download iC Navigator (or any client applet). The application knows about the enabled Lookup Service on Alpha, and so the client PC will be able to see all devices and services registered on both Alpha and Bravo.
If, however, the PC’s Web browser is pointed to Bravo’s iControl—Startup page, and downloads a client application, the applet will not automatically detect the lookup service on Alpha, and so none of Bravo’s services or devices will be visible on the client PC. In order to enable direct access, type Alpha’s IP address in Bravo’s Service and alarm discovery area—the application will be able to find the lookup service, and therefore see everything on Subnet A.
