IBM Cognos Dynamic Cubes

Chapter 5. Administering dynamic cubes 125

2. Select View recent messages to check the progress of the refresh (Figure 5-17). The

window indicates either a success message or a failure message, as applicable.

Figure 5-17 Cache refresh status messages

5.4 Setting up routing rules

If you are setting up your IBM Cognos BI deployment to address applications that are sourced

from Dynamic Cubes and other sources in a mixed environment, you must create server

groups and dispatcher routing rules to ensure that queries are routed to the correct report

server. The reason is because the QueryService that has a dynamic cube enabled is where

the metadata and other cached data items are located. If dynamic cube application queries

are sent to the wrong report server, an error message is returned rather than the requested

data.

For more information about setting up server groups and routing rules, see the “Advanced

Dispatcher Routing” topic in the Cognos Business Intelligence Administration and Security

Guide at the Cognos 10 Information Center:

http://www-947.ibm.com/support/entry/portal/documentation/software/cognos/cognos_b

usiness_intelligence?lnk=msdTS-docu

5.5 Setting up redundant cube instances

To enable load balancing and optimize query performance in high-load environments, you can

set up multiple instances of the dispatcher with identical cube configurations.

When the query is submitted by the user, it will be routed to the next available dispatcher,

making sure all dispatchers are load-balanced. As your requirements changes, you can add

or remove dispatchers from the server group to match your performance needs.

Because queries are routed to different dispatchers based on load, you must ensure that all

instances of the dynamic cube on all dispatchers are operating correctly. If a query is routed

Note: Because data cache is closely associated with the member cache, refreshing the

member cache automatically causes the data cache to be refreshed.

126 IBM Cognos Dynamic Cubes

to a cube instance that is down, the query will fail. In such cases, the queries might seem like

they are failing randomly, complicating problem diagnostics.

To avoid disrupting query execution, adding and removing cube instances must be done in a

controlled way. Before making the instance of the cube in a particular dispatcher available to

the server group, ensure that this dispatcher is

not a member of the server group. This way, no

queries can reach this dispatcher during addition or removal, which will eliminate the risk of

disrupting query execution.

After the cube instance is configured and is running, use the following steps to add the

dispatcher instance to the server group:

1. In IBM Cognos Administration, navigate to the System window (Figure 5-18).

Figure 5-18 System administration tab

2. In the Scorecard view, click the name of the server that holds the dispatcher instance that

you are configuring. Click the down arrow next to the dispatcher address and select Set

properties, (Figure 5-19).

Figure 5-19 Dispatcher instance menu