VADA obtains information to help you discover your application topology by running a System Center Operations Manager (SCOM) agent task on the machine in your deployment you request. If anything goes wrong, the error details are returned in the VADA user interface to help you diagnose any issue.
This article is to help you with troubleshooting any issues you may experience whilst using VADA.
If you see a message
Discovery error or
Discovery is disabled see Discovery Error or Discovery is disabled
SQL servers or databases may not be discovered when used on a failover cluster or Always On Availability group
This is currently a known issue, due to SCOM Windows Computer discovery only occurring once in a 24 hour period, and the SQL listener IP moving from server to server.
Databases and SQL instances cannot currently be discovered on SQL 2017 and 2019. These can be added manually, see Undiscovered Nodes and components.
The user has not been granted permission in SCOM to execute the
Get Netstat CSV (Data On Demand) task (for example, they are a Read-Only Operator). A SCOM administrator will need to modify their permissions.
In order to discover correctly on Unix and Linux systems, the Get Netstat CSV task (upon which VADA depends) must be able to execute ps and netstat with root privileges.
If you have not correctly configured privileged access for the SCOM Unix/Linux agent (either misconfiguring the account assigned to the UNIX/Linux Privileged Account profile, or the server's sudoers configuration), you may receive errors such as:
sudo: no tty present and no askpass program specified
StdErr:ERROR: Process ID list syntax error.
When viewing the task output (see below) you may see the PID, ProcessName, and ProcessDescription columns empty.
Check with the administrator for that system to ensure that the privileged account bound to the UNIX/Linux Privileged Account run as profile is configured correctly, is distributed to the appropriate resource pool, and that the user account in use has the correct sudoers configuration.
When browsing to the Topology perspective of a distributed application in Squared up, you may see a message indicating that the distributed application (DA) cannot be displayed:
This Distributed Application cannot be displayed. Only Distributed Applications that contain Component Groups can be displayed
VADA discovery depends on being able to run the "Get Netstat CSV (Data On Demand)" task on the machine of interest. Trying to run this task separately can sometimes give more useful information to help diagnose what the problem is.
Navigate to the server object in Squared Up which is causing the discovery errors and perform the following four steps:
- Click the task button
- Select Get Netstat CSV (Data On Demand) task
- Click execute
- Observe the output below
- Under the Monitoring tab click on the Windows Computers or Unix/Linux Computers view as appropriate.
- Locate the server which is causing discovery issues
- In the Tasks pane on the left, locate and click on Get Netstat CSV (Data on Demand)
- Click the Run button at the bottom of the window. When the task completes, check the Task output pane for information.
If you need further assistance please contact Squared Up Support and reply to the automatic response with the output of the Squared Up Diagnostics and any discovery error messages (the "copy" button will put them in your clipboard for convenience).