Well on any client, the VUM plugin will not download at all. It hangs at 0% until an error is thrown. "Unable to connect to the remote server".
I was able to get VUM plugin to download and install in the client on the vcenter server itself though. It kept throwing an error about SSLCertificate. So I uninstalled vmware update manager completely, then reinstalled it. Now it works, but only on the client within the vcenter server. The Windows 2008 R2 firewall is disabled, so theres nothing blocking communication from vcenter to other workstations, but the plugin will not download anywhere else.
Then for SRM I was getting error 503 Service Unavailable. I uninstalled SRM completely and then reinstalled it. Now from my client when I try to download the plugin I get 404 Not Found. If I try to download the SRM plugin from vsphere client on the actual vcenter server, I get 503 Server Unavailable.
I've tried re-installing SRM numerous times and I just can't get it to work at all.
So I started a lab with a new domain, vcenter and esxi server and in a virgin install got the evaluation of vcenter 5.5 and esxi 5.5 working no issues. So that makes me wonder if I should just skip 5.1 and go straight for 5.5. The only issue is that for SRM the storage replication adapter for the EMC sans and nas units drop support for the Celerra NX4. They only support VNX now. But the storage replication adapter for SRM 5.1 still supports the EMC Celerra NX4, which is what I have at the DR site. At the production site I also have an NX4, but I have a new VNX5200 sitting in boxes waiting for time to schedule a deployment and migration.
So if I go to 5.5, I have to break the existing Celerra replicator connection and deploy the vmware replication appliance. That sounds like a nice feature since its storage agnostic, but its a re-architect from what is running today. Not to mention to start fresh with a few TB's of data over a 40mbps WAN link, it will take months to get back in sync. Therefore my initial upgrade path was from 4.1U3 to 5.0 (you have to at least go to 5.0 for SRM) and then 5.0 to 5.1. Maybe I can slowly transition vmware replication in and once things are moved to it, I can eventually go to 5.5.