Disk format change going from 6.x to vSAN 6.6?
Internally I received a comment around the upgrade to 6.6 and the disk format version change. When you upgrade to 6.6 also the version of disk changes, it goes to version 5. In the past with these on-disk format changes a data move was needed and the whole disk group would be reformat. When going from vSAN 6.2 (vSphere 6.0 U2 that is!) to vSAN 6.6 there is no data move needed. The update is simply a metadata update, and on the average cluster will take less than 20 minutes.
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