Hi, issac.
Here are steps I often use to clean up my lab.
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Performance Data
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1. Open data_engine probe in Admin Console.
2. Set clean up policy
Delete Raw data older than 1 day.
Delete historic data older than 2 day.
Delete daily average data older than 3 day.
3. Leave it running for several days.
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Alarm
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1. Deactivate NAS probe.
2. Delete <nas>/*.db files
3. Drop NAS_XXXX tables (except for nas_database_migrations) in UIM database.
4. Activate NAS probe.
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Inventory
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1. Open Probe Utility Window for discovery_server probe.
2. Execute "remove_all_master_devices"