Hi,
For referenced management pack, the ID is used. Mostly, for a new environment, we need to import the new sealed MP (in our case, for SCOM2019, not for SCOM2012R2) and the unsealed (that is exported from SCOM2012R2 for overrides) in the new environment.
Mostly, the ID will not change, so the overrides works as expected as in the old environment.
To check the imported unsealed MP from old environment, if we remember the monitor/rule name, we can also check them from the operations console, as shown below:
Regards,
Alex
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