Single Sign On upgrade Sequence 5.1 to 5.5 (multisite and linked mode)

Hi There,

I'm trying to find SSO upgrade documentation that outlines the options that I must select for the following upgrade scenario:

Prior to upgrade to 5.5:

• 2 x 5.1 vCentre servers (Windows 2K8R2) joined by linked mode.
• Each vCentre has its own local SSO server which runs on the same vCentre server. Both have the same Deployment Id.

My understanding it that the upgrade for SSO so Linked Mode will work post 5.5 upgrade should go as follows (obviously linked mode has been removed prior to the upgrade):

1. On the first SSO server. Upgrade from 5.1 to 5.5 using the MULTISITE option. (Followed by Web Client, Inventory Service & vCentre Server).
2. On the 2nd SSO server. Upgrade from 5.1 to 5.5 using the MULTISITE option. (Followed by Web Client, Inventory Service & vCentre Server).

The problem is on the first SSO server when I select MULTISITE option on the next page I enter the details for Partner host and password I've been getting one of the following errors:

1. Failed to get server certificate, or
2. Unable to get host name

And cannot proceed with the upgrade. The only option that works is the STANDALONE vCENTRE SSO SERVER option which I think linked mode wont work post upgrade.

Any help pointing me to a document that highlights the correct options so linked mode is retained post upgrade would be great.

Cheers