Downgrade ESXi 6.7 to 6.5

[EONjohnson]

I have a program that doesn't run on 6.7 yet so I need to downgrade to 6.5 until it is compatible. What is the best method to downgrade please?

[RickVerstegen]

You might check the following KB:

VMware Knowledge Base

ESXi 6.7 is not listed in product version in this KB, so it is probably not supported.

Rick

[EONjohnson]

Thanks for the reply,  It is a new install of 6.7 and not an upgrade from 6.5 to 6.7.  I guess we should have tested it before we did the final install.  The product that is now working correctly is Cloudberry.   They said the backup feature we are trying to use is not compatible with 6.7 yet and they are working on it but don't have a timeline of when it will be done.

[RickVerstegen]

Then your only option will be a reinstall of ESXi 6.5.

[diegodco31]

Downgrade ESXi from version 6.7 to 6.5 is not supported.

VMware Knowledge Base

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[golddiggie · Accepted solution]

Depending on how long it's going to take them to become compatible, go to 6.5u1 (not 6.5u2). That way you'll be able to go to 6.7 with an upgrade/update. Well, at least until 6.7u1 is released (could be during VMworld 2018 in August).

Since this was a new install, your only course of action is to do a clean install. If you already setup vCenter (vCSA or Windows install) that can manage 6.5x hosts. But, if the software runs against vCenter/vCSA, then you have do a reinstall/rebuild of everything on the lower version. If you didn't know, you cannot administrate newer versions of hosts with an older version of vCenter.