In my environment to fully upgrade to vcloud suite 5.5 I would have to use the following order:

A) vCloud Director
B) vCNS (vShield Manager)
C) vCenter
D) ESXi hosts
E) vShield Edge

 

In this post I will be discussing the process of upgrading the ESXi hosts from 5.1 to 5.5

1) In vCloud Director disable the host by going to Manage & Monitor  -> Hosts -> Right click host -> Disable Host . This stops any VCD VMs being created or migrated onto this host

2) Put the host into maintenance mode (Normaly I would click Redploy All VMs. but the documentation suggests that you should let vSphere do this.)

3) Upgrade the host via your desired mehtod. (eg Update Manager, interactive install etc)

3) Upgrade the host agents

Note: This didnt work for me and I had to Unprepare Host then Prepare Host 

5) in vCloud Director enable the host again by going to Manage & Monitor  -> Hosts -> Right click host -> Enable Host ​

6) Take ESXi host out of maintenance mode