On Thu, Oct 6, 2016 at 11:41 AM, Simone Tiraboschi <stirabos@redhat.com> wrote:

[snip]

In every case the upgrade to 4.0 is requiring that all your cluster and all your data center should be at 3.6 compatibility level before the upgrade.
From the error you got, it seams that you still have something at 3.5.

[snip]

And in any case this can be your friend for dependencies in updating datacenters/cluster to 3.6:

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Virtualization/3.6/html/Upgrade_Guide/chap-Post-Upgrade_Tasks.html

For their general concepts (in 3.6):

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Virtualization/3.6/html/Administration_Guide/chap-Data_Centers.html

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Virtualization/3.6/html/Administration_Guide/chap-Clusters.html

HIH,

Gianluca