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CTK and multi-writer flag


I would like to know some details regarding CTK and the multi-writer flag not being supported.

If my disk A,B, C are used as multi-writer and shared, can I still enable ctk on disks D,E, F ( given that i won't enable/add ctkEnabled = "TRUE" parameter on configuration file )

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Hot Shot
Hot Shot


according to this https://kb.vmware.com/s/article/2110452
seems you need to disable the CBT for all the disks of the VM is not explicitly said if you can do only for the multi-writer disks. Seems a security measure that is by default set on false with esxi 7.0.

I remember that we had a similar issue moving from 6.7 to 7.0 and the only solution was to apply this KB.

  1. Power off the virtual machine.
  2. Right-click the virtual machine and click Edit Settings.
  3. Click the Options tab.
  4. Navigate to the Advanced section and click General.
  5. Click Configuration Parameters. The Configuration Parameters dialog opens.
  6. Click Add Row.
  7. Add the ctkEnabled parameter and then set its value to true.
  8. Click Add Row, add scsi0:0.ctkEnabled, and set its value to false. Do this for each active disk on the virtual machine, using the correct SCSI address for that disk.
  9. Power on the virtual machine.
  10. In the home directory of the virtual machine, verify that each hard disk is not associated with a vmname-ctk.vmdk file, where vmname is the name of the virtual machine.
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