Find activity logs sent to a log analytics workspace via a diagnostic setting

@Khushika Shringi - Welcome to Microsoft Q&A and thanks for reaching out to us.

The query you used, search * | where TimeGenerated == "z", will not return any results because it is filtering for events that occurred at a specific time, which is not likely to match any events in your logs.

To search for the exported activity logs of your HDInsight cluster, you can use the following query:

AzureActivity | where ResourceProvider == "MICROSOFT.HDINSIGHT"

This query searches for all activity logs related to HDInsight clusters.

Please try the above and see if it helps.

Hope this helps. and please feel free to reach out if you have any further questions.

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