Excessive number of subnodes

An excessive number of subnodes in the Application Management Console workspaces in the Tivoli Enterprise Portal can be caused by a number of configuration issues.

Symptoms

Symptoms of excessive subnodes may include:
  • Blank All Applications workspace with error BWMRA0556W.
  • Error message KFWITM217E in the Tivoli Enterprise Portal Server log.
  • Frequent disconnection from the Tivoli Enterprise Monitoring Server because the total number of characters in the application names exceeds the limit of 32 767 characters. Other symptoms may include: Tivoli Enterprise Monitoring Server and agent crashes; or IBM Tivoli Monitoring not behaving as expected.

Causes

Generally, the symptoms listed above are caused by inappropriate data gathering settings, including:
  • For Web Response Time, application name reporting rules which identify too many uniques URLs, resulting in a large number of unique application names. The Application Management Console creates a subnode for each unique application name, which results in complex tables in the Tivoli Enterprise Portal.
  • If the tracking topology is not fully resolved when the Application Management Console collects data from the Transaction Reporter, nodes which have not yet been determined are treated as root nodes and are created as subnodes under Applications in the Navigator. These nodes remain active for at least 8 hours before they are made inactive, even though they may not be part of the real topology discovered during this time. For these spurious subnodes, the Overall Status column in the Application Status table displays a value of None but the subnode is still displayed in the Navigator.
    Application Status table in the AMC workspace

    If there is no activity for 8 hours, the subnodes are marked inactive and the corresponding rows are removed from the Application Status table. The offline subnodes remain in the Navigator until they are cleared manually.

Reducing the number of subnodes

There are a number of ways you can reduce the number of subnodes created by the Application Management Console:
  • Customize the reporting rules for Web Response Time to reduce the number of application names:
    1. In the Application Management Configuration Editor, select Web Applications > Web Response Time > Web Transactions.
    2. On the Reporting tab, change the value in the Application field to a value that is as specific as possible, with a minimum number of wildcards.
  • Reduce the amount of raw data collected by including data only from those agents which supply root node data.

    For example, where Web Response Time tracks HTTPS requests to an iPlanet web server, which then redirects requests to Web Logic application servers tracked by ITCAM for J2EE, with both sending Transaction Tracking API events, the root nodes come only from Web Response Time. In this example, use the ITCAM Console to exclude data from the other agents.

    ITCAM Console screen capture showing False for "Exclude Web Response Time agent data collection" and True for all other agents
  • If you receive error BWMRA0556W or KFWITM217E, increase the maximum allowable number of subnodes in IBM Tivoli Monitoring. See Tivoli Enterprise Portal Server troubleshooting. Ensure that the total number of application names does not then exceed the limit of 32 767 characters.
  • If there are many inactive subnodes, clear the offline entries:
    1. In the Navigator in the Tivoli Enterprise Portal, right-click Enterprise and select Workspace > Managed System Status.
    2. In the Managed System Status table, select the offline systems, right-click and select Clear offline entry.
Tip: You can use a situation to alert you to when the number of application subnodes exceeds a set limit. For example, use the Situation Editor to create an alert for when the number of application subnodes exceeds 200. (If the length of application names is less than 160 characters on average, 200 application names should not reach the 32 767 character limit.) Use the AMC Application attribute group and the Application Key attribute item.
Situation editor illustrating information in text.