Running Horizons 7.4 on vsphere 6.5 U2. Want to upgrade horizons to 7.12. Can I do a straight upgrade to 7.12?
Security servers are currently used, upgrade connection server first then security servers?
Yes you can, however when upgrading from a version of Horizon 7 earlier than Horizon 7 version 7.8, some user authentication settings will change. How these user authentication settings affect the user experience depends upon the client. See the Horizon Client documentation at https://docs.vmware.com/en/VMware-Horizon-Client/index.html.
Update sequence is detailed here : VMware Knowledge Base