During the NSX upgrade process, core dumps located in the /var/log/core directory on NSX Edge are removed.
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This is an expected behaviour. During the NSX upgrade process, any existing Edge Core Dump files are removed.
If the NSX Manager receives an Application Crashed event from the Edge node and a Root Cause Analysis (RCA) is required, ensure to collect the Edge support bundle with core dumps before initiating the NSX upgrade.
To do this:
Navigate to NSX Manager > System > Support Bundle.
Toggle the switch to include core files and audit logs to ensure the Edge core dump files are collected as part of the support bundle.
For more details, refer to the following articles: