Downgrade from v5 to v4

[ncmsvmware]

Dear All,

We upgraded our vCenter from V 4 to V 5 AND vSphere from ESX 4 to ESXi5, but now we need to know how we can downgrade:

• From vCenter  v5 to v4
  
• From ESXi 5 to ESX 4
  

What are the impacts that we can face?

If you have any documentation or link regarding this, please share it with us.

Thanks

Regards,

Naeema

[aravinds3107]

Is there any specfic reason to downgrade the enviroment?

Probably you would had already upgrade your datastore to VMFS5 and Vm hardware version to 5 either of this would support on vSphere 4.x version so you have to perform a fresh build of host and use Vmware Converter to move the VM's as this would give the option to change Vm hardware version

You can check this thread for some of the suggested things http://communities.vmware.com/message/1875156

[firestartah]

Hi

As Aravind said, the upgrading will mean your datastores might not be compatible in vSphere 4. You have already upgraded your vCenter database which can't be downgraded. Your vm may be on vm hardware version 8 which isn't supported in vSphere 4. There is no way of downgrading from ESXi5 to ESX4 so that will mean a complete rebuild.

Personally i would highly recommend against it as it will essentially mean you will have to rebuild your entire environment. Is there a reason you want to go back?

Gregg

[Lessi001]

Hello Naeema,

whats the reason for downgrade considerations?

The upgrade process from 4 to 5 is a one-way street - so downgrading will result in restoring backups or build up a new environment with vsphere 4.

Have you also already updated the datastores to vmfs5?

Regards

Andreas

[ncmsvmware]

Thanks for your reply. There is no specific reason, but I need to know just in case we faced issues.

What I need is to know the procedures to downgrade?

Regards,

Naeema

[ncmsvmware]

Thank you. How can I know if our VMs are on VM hardware version 8?

There are no specific reasons for tha, just we need to know

[firestartah]

Well try not upgrade any of your host virtual hardware to version 8 on an of the datastores to VMFS 5 before being confident in the upgrade. Also take a snapshot of your vCenter server before the upgrade and a backup of your SQL DB. That should make it easier to roll back if something went wrong. Which is really shouldn't as the upgrade is very basic and worth it.

Gregg

[ncmsvmware]

Thanks, I am not sure if the data stores are updated to vmfs5? how can I check that?

We are using SAN storage for the cluster,

[firestartah]

Hi

You can tell via VUM which is the simplest way but firstly you will know if you upgrade the vm hardware for your virtual machines as you will need to shut down the virtual machines to upgrade them. You can see a vm's hardware version by clicking on the host and under the summary it will detail the VM hardware version as "VM version" as shown in the diagram attached.

[firestartah]

the upgrading of the datastores is also something you would remember but you can see their version by clicking on a host that has access to all the datastores and clicking the configuration tab at the top and then the storage link and it will show you in one of the columns as shown in the attached screenshot

[firestartah]

Marked as assumed answered, please allocate points for helpful answers and correct answers

[EdWilts]

I don't think anybody answered this particular point yet.  You can not downgrade vCenter without first downgrading the hosts.  A vCenter 4 system can't be used to manage an ESXi 5 host but a vCenter 5 can be used to manage an ESXi 4 host.

My recommendation would be to upgrade vCenter first and let it sit for a while managing your version 4.x hosts.  After you're comfortable with this configuration, then upgrade your hosts.

[herseyc]

Think it should be stressed that a downgrade of vCenter or ESXi is not really an option.  Downgrading would mean a reinstall of the hosts and vCenter.

Make sure you back up your vCenter database and your ESX/ESXi configurations before you upgrade to 5.

Thanks

Hersey