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Troubleshooting if hosts vanish during a vCenter update

Troubleshooting if hosts vanish during a vCenter update

Owned by Robin Gierse
Last updated: Jan 13, 2025 by Matthew Hierholzer

This article explains why hosts may vanish after a vCenter update.

LAST TESTED ON CHECKMK 2.3.0P1

Table of Contents

Problem

When updating a vCenter, hosts  added by DCD (Dynamic Host Configuration) may disappear.

Reason

The piggyback data from vCenter is not updated, causing the DCD to delete hosts that do not receive data within the configured time frame.

Solution

To mitigate this issue, disable the DCD connection to vCenter prior to the update and re-enable it afterward. This prevents the DCD from deleting hosts due to a lack of updated piggyback data during the update process. Disabling the connection ensures that no data discrepancies occur while the vCenter is being updated.

The following side effects have been observed at the time of writing:

  • Affected hosts lose their agent update registration.