Good News if you use ESXi 5.0 or ESXi 5.1 – the CBT Bug is fixed for these versions.

Unfortunately there is no fix available at the moment for ESXi 4.x and 5.5.

If you do not know about this issue you can read my previous post or VMware KB 2090639: QueryChangedDiskAreas API returns incorrect sectors after extending virtual machine vmdk file with Changed Block Tracking (CBT) enabled

Here you can find the patch for

If you use ESXi 4.0 or 5.5 you can only use the following workarounds for the issue:

  • perform a Storage vMotion after having extended the CBT-enabled disks past a 128 GB boundary
  • or you disable and re-enable CBT after extending past the boundary:
  1. turn off CBT
  2. take a snapshot
  3. delete the snapshot
  4. turn on CBT
  5. take one more snapshot
  6. last but not least delete the snapshot


Do you know how you can restore a virtual machine (eg. your vCenter server or vCenter DB Server) with TSM directly to an ESXi host when your vCenter Server is offline?

Here is a short how-to:

  • start the IBM Tivoli Storage Manager
  • open “Edit” – “Client Preferences”
  • change to the tab “VM Backup”

There you will find the configuration for “VMware Virtual Center or ESX Server”:

  • overwrite the field “Host” with the IP address of the standalone host
  • provide the username for the host (eg. root)
  • provide the password for the user
  • press “Apply”
  • re-open the Tivoli Storage Manager to become these changes effective

TSM restore esxi

  • open “Actions” – “Restore VM”
  • select the VM you want to restore
  • click “Restore”

A wizzard will open – choose “Restore to Following location”:

Fill in the following fields:

  • Name: display name of the VM you want to restore
  • Datacenter: ha-datacenter
  • Host: FQDN of the ESXi host you want to restore
  • Datastore: exact name of the datastore

TSM restore esxi2

Important: to restore a VM directly to an ESXi host you have to fill in “ha-datacenter” in the Datacenter-field!!!

Else you will get an error “ANS14166E Creating a Virtual Machine, but the datacenter was not found”


To start the restore process press “Restore”


You may need to disassociate an ESXi host from vCenter in a situation where your vCenter Server is not available (eg. to perform an Emergency Restore of a VM directly to an ESXi host).

If you use vSphere 5.0 or above just follow these steps:

  • connect directly to your ESXi host using the vSphere Client
  • select the ESXi host in the left inventory panel
  • change to the “Summary” tab
  • scroll down till you see the “Host Management” section

In the “Host Management” section you have two possibilities:


  1. Reconnect vSphere Client to this vCenter Server…
  2. Disassociate host from vCenter Server…

Choose number two: “Disassociate host from vCenter Server…” – Done!

VCP-DCV-smGood News: the chance to renew your VCP5-DCV credentials for two more years with passing the VCP5-DCV Delta Recertification Exam was extended until March 10, 2015!

Since VMware has changed the recertification policy for VMware Certified Professionals (VCP) earlier this year, you have to take care that you renew your credentials within two years.

If you have to renew, this will be the quickest and easiest route to recertification!

The Delta Exam has some big advantages:

  • you can take it online from any location – no need to visit a Pearson VUE testing center
  • favorable price: exam costs about 120 US-Dollar
  • you extend your VCP cert for two more years relatively easy

Interested? Take a look at these links and pass the exam:

Good Luck!