I was wondering if this is possible and what is the syntax using the vmkfstools and if it would destroy any VMs sitting on the existing partition. I am assuming that it wouldn't harm them considering that the upgrade package does this when upgrading from 3.x to 3.5. Thanks.
Are you sure the upgrade package does this? As far as I know the VMFS filesystem isn't touched. Only new datastores are formatted with 3.31. I looked into the vmkfstools and also couldn't find a way to upgrade it to 3.31. Only option is to upgrade from 2.x to 3.x.
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