Troubleshooting RES Wisdom connections

When a RES Wisdom Agent appears to be offline in the RES Wisdom Management Console, while you are certain it is up and running, where do you begin troubleshooting?

A RES Wisdom Agent appears online in the RES Wisdom Management Console after succesfully discovering one or more Dispatchers and registering itself and logging on to the database. Since the Agent cannot communicate with the database directly, the ability to discover Dispatchers is crucial because they set up the connection to the database.

Dispatcher discovery can be done through Autodetect, a Dispatcher Address List or a combination of both. If you use Autodetect your network switches must support Multicast otherwise it will not work. The following troubleshooting actions can be performed in either discovery method.

To begin with, it couldn’t hurt checking your network connectivity, so start by pinging your Dispatcher(s). If you are using a Dispatcher Address List instead of Autodetect, you should ping to the same name you are using in the Dispatcher Address List to avoid missing name resolution problems. For example, if you are using a NetBIOS name or FQDN in the Dispatcher Address List but you happen to know the IP address of the Dispatcher by heart, you shouldn’t use the IP adress in the test because then you already resolved the name to an IP address and won’t notice it if the Agent is not able to do so.

RES Wisdom Agents communicate with Dispatchers using port 3163 TCP so the next step is to check whether this comunication channel is open. This can be done rather easily by opening a command prompt on the Agent and typing the following command followed by enter: ‘telnet DISPATCHER 3163′, where DISPATCHER is the name of the Dispatcher according to the Dispatcher Address List. This test should return an empty Command Prompt window displaying nothing but a blinking cursor.

If this test is succesful the communication path between the Agent and the Dispatcher is in working order. If this test fails either the Dispatcher service is not running properly or there is something blocking the comunication. Restart the Dispatcher service and/or check for firewalls that block traffic to this port.

Next step is to check the Dispatcher Discovery process. For this process it is necessary to distinguish between the settings the Agent should have got (Global Settings), the settings the Agent received earlier (Agent Settings) and the settings the Agent is actually using (Agent registry) to try and find a Dispatcher.

The Global Settings can be found in the RES Wisdom Management Console and are the default settings for all Agents.

In the RES Wisdom Management Console it is possible to set custom settings on a per Agent basis so you should always check what settings the Agent has by double-clicking the Agent and view the Settings tab. Whenever an Agent is online it will check these settings regularly and overwrites its registry settings if necessary.

Whenever an Agent starts the Dispather Discovery process it uses the settings stored in the registry under HKEY_LOCAL_MACHINE\SOFTWARE\RES\Wisdom\Agent

So, at first an Agent needs to be able to connect to a Dispatcher with the settings stored in the registry. After connecting succesfully it will check whether its settings in the database have changed and overwrite the ones in the registry when needed. The Agent settings in the database can differ from the Global Settings.

With this in mind about 75% of the connection problems can be solved. For the remaining 25% we need to dig in a little deeper into the Dispatcher Discovery process but I will cover that in another blog article.

To be continued…