Siebel Server Installation Guide for UNIX > Implementing Load-Balancing with Central Dispatch > Planning Your Central Dispatch Site >

Network Connectivity for Central Dispatch

To establish network connectivity among all nodes in your Central Dispatch site, complete the following tasks:

Assigning the Enterprise Virtual IP Address

Select the Siebel Enterprise (VIP) and register it with the appropriate naming service. Record the VIP in Deployment Planning Worksheets.

When you deploy Central Dispatch on your Siebel Servers, Siebel Web Server Extensions connect the Web servers to a virtual IP address for the Siebel Enterprise (VIP), rather than connecting directly to the Siebel Servers. The Central Dispatch scheduler uses the VIP to connect Web servers to the most appropriate, and least loaded, Siebel Server in the Enterprise.

To obtain a static IP address to use as the VIP, see your network administrator. The VIP should be unique and should be used exclusively as a logical IP address. Never assign a VIP to a real physical host, or computer.

You must register your VIP with the appropriate name services, such as DNS or NIS, exactly as you would any other IP address. However, unlike standard IP addresses, the VIP denotes the entire Central Dispatch site, not just a particular server. Make sure that all the nodes in your Central Dispatch site are registered with the naming service you are using. For example, if you use hosts files, each file must contain entries for all the nodes in the site.

TIP:  If a group of servers is cut off from the rest of the network and visible only to each other, resolve their names either by modifying the DNS database records or by modifying the entries in the local host file:

      /etc/hosts

If this is not sufficient to establish connectivity, contact your network administrator to make sure that all physical connections are in place and that routing tables have been updated correctly.

Assigning Static IP Addresses

Assign static IP addresses to each machine in the Central Dispatch site. Select these addresses from the appropriate subnet, and record this information in Deployment Planning Worksheets.

Central Dispatch requires that static IP addresses be assigned to each of the machines with which it interacts. These IP addresses must all use the same subnet mask. The IP addresses of the primary and backup scheduler nodes must be on the same subnet as the VIP.

To assign static IP addresses to your UNIX servers

  1. Follow the documentation provided by your hardware and operating system vendors to configure each network adapter card with the appropriate static IP address.
  2. Double-check to verify that each static IP was assigned to the correct machine and that no static IP was assigned to more than one computer.
  3. Verify that the Gateway VIP was not assigned to any network adapter card.

    4. CAUTION:  If the DNS Server address is selected by default, do not deselect it because you will not be able to access the network.

Verifying Network Routes

Use the traceroute utility to verify that all servers have TCP/IP connectivity to one another, as well as to the servers that will support the Siebel Database Server and the Siebel File System.

Verify that the routes between all servers are symmetric. Symmetric routes are routes that, step for step, traverse the same computers and the same network nodes in exactly the opposite order with respect to each other.

TIP:  If all servers are in the same subnet, the routes will always be symmetric.

To verify that routes between servers are symmetric

  1. On the computer that will support the primary Central Dispatch scheduler, open a shell command window.
  2. Use the traceroute command to display the route from it to one of your servers:

    3. $ traceroute server

    where:

    server = The name or IP address of the Siebel Server machine for which you are testing symmetry.

  3. From that computer, open a shell command window and use the traceroute command to display the route from it back to the machine that will host the primary Central Dispatch scheduler.
  4. Compare the results of each traceroute and verify that the routes between these servers are symmetric.
  5. Repeat these steps from your primary Central Dispatch scheduler for each server on which Central Dispatch has been installed.
  6. From the secondary Central Dispatch scheduler, repeat this process with each server.

If you find asymmetric routes between any two servers, adjust the routing so that the routes are symmetric. You might have to delete static route tables and redo the routes, or restart the router in order to get a symmetric route.

After you have verified network routes on all machines, you are ready to install Central Dispatch.


 Siebel Server Installation Guide for UNIX 
 Published: 24 June 2003