I have seen quite a few questions come in on how to properly upgrade from an existing vCenter Server Appliance (VCSA) 5.x and/or 6.x environment to the latest vSphere 6.0 Update 1 which was just released today. Before I jump straight into the process, I think its worth covering on how updates (patches) and upgrades have traditionally been handled for the VCSA. In an update or patch scenario, you are staying within a major release of vSphere (e.g. vSphere 5.0) and moving to something like vSphere 5.0 p01 and in this case, an in-place update or patch is performed. In an upgrade scenario, where you are moving from one major release (e.g. vSphere 5.0) to another major release (e.g. vSphere 6.0), a "migration based" approach is taken. This means that you would need to deploy the new VCSA that you wish to upgrade to and then migrate the data from your old VCSA appliance to the new one which is part of the upgrade workflow. This "migration based" approach was also true for any "U" (Update) releases (e.g. vSphere 5.5 to vSphere 5.5 Update 1). 

For major releases, this makes perfect sense and provides customers a nice way to easily rollback if something goes wrong. You simply power off the new VCSA and then power on your original VCSA and you are back in business. For update releases, we have heard from our customers that this process was not ideal and though there is always a risk when updating software (which is why I always recommend customers test thoroughly in a Dev/Test environment before moving to production), the amount of changes in the code is significantly less when compared to a major upgrade. One of the new features that we have introduced in vSphere 6.0 Update 1 is an in-place upgrade for "U" (Update) releases which I have already blogged about here among other new features.

This means that if you are coming from a VCSA 6.x environment and you wish to upgrade to vSphere 6.0 Update 1, you simply just mount the vSphere 6.0 Update 1 Patch ISO to your VCSA 6.x environment and perform the update from the command-line via the appliancesh interface. This is quite nice as it reduces the need to copy data between your old and new appliance and helps reduce the overall downtime. In fact, you can upgrade to vSphere 6.0 Update 1 in about 10min or so using this new method. If you are coming from a VCSA 5.x (5.0, 5.1 or 5.5) environment, this would be consider a major to major upgrade and you would need to follow the "migration based" approach to upgrade to vSphere 6.0 Update 1. One other thing to note after you have upgraded to vSphere 6.0 Update 1, we have now re-introduced URL based patching via the VAMI interface. This means in the future, you no longer need to update or patch from an ISO but can do so directly from VMware's online repository.

Below are the instructions on upgrading from VCSA 6.x to VCSA 6.0 Update 1:

Note (09/14/15):

• If you have an External PSC with your VCSA 6.x and wish to upgrade, the process shown below is the same for both the PSC and the VCSA. You will want to first upgrade your PSC first as that provides authentication to your vCenter Server. Once the PSC has been upgraded and accessible on the network again, you will then want to move to your VCSA. If you are interested in the proper sequence and ordering of VMware Products to update, you can also check out this handy VMware KB 2109760 which provides all the details
• Thanks to fellow reader Idan for reporting this but it looks like after an upgrade of the VCSA, the default VMware URL for the VAMI is not working. You will need to update it to point to the following URL https://vapp-updates.vmware.com/vai-catalog/valm/vmw/647ee3fc-e6c6-4b06-9dc2-f295d12d135c/6.0.0.10000.latest/ instead of the default one as shown in the screenshot below. This is only applicable for upgrade scenarios. If you deploy a new VCSA 6.0 Update 1, it will automatically be using the correct URL

Step 0 - Ensure you have a proper backup and take a snapshot of your VCSA 6.x appliance before beginning.

Step 1 - Download the VCSA 6.0 Update 1 Full Patch (VMware-vCenter-Server-Appliance-6.0.0.10000-3018521-patch-FP.iso) by visiting the VMware Patch Download site.

Step 2 - Mount the VCSA 6.0 Update 1 Patch ISO to your VCSA 6.x appliance using either the vSphere Web/C# Client

Step 3 - Login to your VCSA 6.x appliance via SSH to the appliancesh interface. If you have disabled that, simply type "appliancesh" and login with the root credentials.

Step 4 - Run the following command to stage and install the patches from the VCSA 6.0 Update 1 Patch ISO:

software-packages install --iso --acceptEulas

Note: If you run into any errors while either staging or installing the patches, you should drop into the bash shell and take a look at /var/log/vmware/applmgmt/software-packages.log file for additional information. One common issue that I have seen in the past is if your /storage/log partition is full and you may need to perform a clean up before continuing.

Step 5 - Once the upgrade has completed, you just need to reboot your VCSA by running the following command:

shutdown reboot -r "Updated to vSphere 6.0u1"

Step 6 - A quick way to confirm that you have successfully upgraded your VCSA to vSphere 6.0 Update 1, simply open a browser to the following URL: https://[VCSA-IP]:5480 and it should take you to the new HTML5 VAMI interface.

If you would like additional information, take a look at this VMware KB 2119924.