Troubleshooting Tip: 'Disk Partition size mismatched' messages logs during upgrade

During the upgrade, the FortiGate or FortiProxy console may display the following messages:

b3-1 wcs_read_and_compare_metadata:2559 ERROR: Disk Partition size mismatched ! E/R (632654964736 / 632650724352)
a3-0 wcs_read_and_compare_metadata:2559 ERROR: Disk Partition size mismatched ! E/R (632654964736 / 632650724352)

These messages occur when the disk metadata read from storage does not exactly match the values expected by the system. As indicated in the error output, there is a difference between the Expected and Read (E/R) values, which reflects a metadata mismatch rather than an active disk failure.

Such messages are not a concern when they appear due to one of the following conditions:

• The disk has been formatted.

• The disk configuration has changed.

• The disk daemon version has changed as part of a firmware upgrade.

During an upgrade, changes in disk handling logic or daemon versions can result in previously stored metadata differing from the recalculated values, causing these messages to be logged.

To confirm that the message is benign, restart the WACS daemon using the following command:

diagnose wacs restart

If the disk partition size mismatched messages do not reappear after restarting the daemon, this confirms that the messages were triggered by an expected upgrade-related condition and no further action is required. Further investigation is only necessary if the messages appear again. Reach out to the TAC for technical assistance if the messages appear again.