Debugging a pattern when CI doesn't exist in CMDB

[Saketh]

When a user tries to debug a pattern by providing the device info., if the CI doesn't exist in the CMDB horizontal discovery is triggered on the CI. If horizontal discovery fails during classification/identification, the CI record will not be created and the user will not be able to debug the pattern.

For example: Let's consider a windows device with IP: 10.x.x.x which doesn't exist in the CMDB. When the user tries to debug Windows OS - Servers pattern, HD is triggered and the pattern fails during the scan. The user will not be able to debug the pattern. 😞

Now how do we debug this??

One solution is: Create a dummy CI with class name that matches the pattern's ci type. For example, to debug a failing Windows OS - Servers pattern, create a CI with class -> cmdb_ci_win_server with ip address of the device you want to debug.

Now when you try to debug, the pattern engine will:

1. find the CI in the CMDB

2. skip running Horizontal Discovery

3. allows the user to debug the pattern

[Vivektietsood]

Isn't it easier for you to fix the error ? What is the error you get ?

[Saketh]

The goal of this article was to provide an approach to debug the pattern when the system doesn't allow. Irrespective of the error, the end-user may want to debug the pattern. In general, when discovery runs, users can see the data as part of the pattern log. But if they want to actively debug the provided approach will help.

This also helps when writing new infrastructure patterns as developers may want to debug as the pattern is being built.