I am doing this in a test lab.
I have AD setup with domain xxxx.local and the Windows Server to be the vcenter is joined to the domain.
My issue is that when i choose to install SSO (fresh) it detects it is joined to the domain, forward / reverse look up works just fine, BUT at the next window it for some reason brings to set password for administrator in the "vsphere.local" domain. That portion is grayed out and i have no idea where this "vsphere.local" is coming into the picture. If ANYONE can advise me on this, please advise. Much appreciated.
vsphere.local is the identity source provided by the vCenter Single Sign-On system, Please refer to SSO Identity Sources section of vsphere5.5 documentation for more information. The password you are asked to provide here is the password for the administrator user(firstname.lastname@example.org) who can administer vCenter Single Sign-On, In vCenter 5.5 by default he also becomes the administrator for the vCenter Server.