Before you begin, make sure that you read the vSphere 6 upgrade guide, the vSphere 6 release notes, the Hardware and Guest OS Compatibility Guide and the Product Interoperability Matrix from VMware before you start the upgrade process. Also, make sure your environment meets the software and hardware requirements as described in the upgrade guide.
Since the vSphere 6 introduces the VMware Platform Services Controller, you should have a look at the vCenter Server upgrade path example as described in the upgrade guide to fully understand the changes in your environment after the upgrade for vSphere 6. For example: I am running a simple installation of the vCenter Server (Inventory Service, Web Client, Single Sign-On) on a Windows Server 2008 R2 virtual machine with Update Manager, Auto Deploy, Dump Collector, Syslog and a Microsoft SQL Server 2008 R2 Express. So according to the upgrade guide, my new vCenter Server infrastructure.
The upgrade of your environment to VMware vSphere 6.0 is performed in a phased manner. The components that are upgraded in earlier phases are fully compatible with components whose upgrades have not yet occurred. – See more at: http://www.vmware.com/products/vsphere/upgrade-center/upgrade.html#sthash.zcolKAMA.dpuf
1vCenter Server 5.5 to 6.0 Upgrade on Windows with Embedded Platform Services Controller
2vCenter Server Appliance 5.5 to 6.0 Upgrade with Embedded Platform Services Controller
3vCenter Server 5.5 SSO-HA Upgrade to vCenter Server 6 PSC
4vCenter Server 5.5 to 6.0 Upgrade with External SSOVsphere 6 Suite Features and Limitation
Great Tutorial Video In-place Upgrade 5.5 to 6.0
Long Distance vMotion, Cross vSwitch and vCenter vMotion
vMotion of MSCS VMs using pRDMs
vMotion now can be routed (L3)
Fault Tolerance of VMs with upto 4vCPU (Network Constraints min 1GbE/CPU still apply)
Content Library (Replicate templates, ISO etc across multiple vCenters)
NFS 4.1 support
Instant Clone (aka VMFork)
vSphere HA Component Protection
Storage DRS and SRM support
Network IO Control per VM reservations
Storage IOPS reservations
Platform Services Controller architecture for vCenter – for SSO , licensing and integrated Certificate Authority
Linked Mode support for vCenter Server Appliance
64 hosts per cluster
8000 VMs per cluster
480 CPUs per host
12TB of memory
1000 VMs per host
128 vCPUs per VM
4TB RAM per VM
Compression of replication traffic configurable per VM
Isolation of vSphere Replication host traffic
vSphere Data Protection now includes all vSphere Data Protection Advanced functionality
Up to 8TB of deduped data per VDP Appliance
Up to 800 VMs per VDP Appliance
Application level backup and restore of SQL Server, Exchange, SharePoint
Replication to other VDP Appliances and EMC Avamar
Data Domain support
Planning for the Upgrade:If you are planning for an upgrade, the first thing you have to do is ensure that there is product interoperability with all the third party tools and plugins that you use everyday. If you are confident that its going to be OK, this is how to plan for it. Ensure you plan and test this on a non-production environment. Stress test the new environment with application VMs and other tests that you generally perform on a green fields environment. Write out your plan. My plan (for my lab is as below)Plan out your SSO deployment model and how to upgrade to the new PSC model. (Always deploy PSC in a HA mode with multiple VMs. It has inbuilt replication and so you don’t have to setup anything for it ).
Snapshot your SSO Server and then Install the new PSC (Platform Services Console) and ensure that SSO and licensing of the existing environment is migrated over. Once everything works, don’t forget to delete that snapshot.
Snapshot the vCenter Server (including the SQL Server and the vCenter DB) and upgrade the components of the Management Platform (vCenter, VUM etc). Delete Snapshot again.
Ensure all the licensing is intact and that you can login with the required permissions. This is paramount to test this as you don’t want to upgrade and then realise that it needs newer permissions etc.
Upgrade your hosts one by one using VUM update.
Test out each of the new features that you want to use in your environment.
Document everything I mean everything this way you can run through all the tests you’ve done and repeat any with less than satisfactory results.
Test all the failed tests after all the components have been upgraded. If it still fails the test, if you have VMware Support for your non-production licenses then log a case with VMware Support.
Once resolved, re-run your tests until all of them are successful.
Great Video on Vsphere 6 Upgrade Options.
Vsphere 6 Upgrade Path and Options.
Vsphere 6 Upgrade Methods
Basic IT You Tube Channel