As I visit a number of my customers, i get a lot of questions about upgrading to vSphere 6.5 and where to start.  I was doing some research and I came across some really helpful info on planning your vSphere 6.5 upgrade.

The fist step of any upgrade is making sure to do your homework and check for any relevant documents such as release notes for each product, vSphere documentation, and the compatibility guide.  These provide important information such as what’s new, known issues and upgrade notes. The VMware Compatibility guide is key.  Don’t assume that something supported in vSphere 5.5 will be supported in 6.5.  You have to double check.  I cant stress enough, you have to check hardware compatibility and make sure its supported prior to the upgrade.  Also check out VMware KB articles, they can be a great source to assist on upgrades. Ill provide links below.

Other planning considerations:

• Know if your vCenter Topology is supported for 6.5
• Check to make sure 3rd party solutions are compatible
• How about an environment health check prior to the upgrade?
• Windows vCenter should be migrated to VCSA
• Map out your upgrade, if its a large environment complete it in phases
• Got Training? Use VMware HOL to get familiar with all the new features and management interfaces. A lot has changed. There is a new vSphere appliance interface, HTML5 vSphere client, PSC management interface, vSphere web and host client. Do you know what client is used for what? You need to know! 🙂

Its really important to take your time planning.  Make realistic goals and time for completions. Work with your extended team, like storage and network and the automation team.  They will most likely have tasks to complete or items to review prior to an upgrade.  No one wants a call at 2am for an emergency because you failed to include your storage team in the upgrade planning. TEST, TEST and TEST AGAIN!  Try and account for all scenarios and any complications that could happen and what to do if you need to back out of the upgrade. What’s the point of no return.  Open an SR with VMware prior to the upgrade to have them aware of when its happening.  Support can make all the difference sometimes.  Do you need backups? Yes, no, maybe.  You need to know.  These are just some of the questions and answers you need, Im betting you will come up with a lot more.  There is a ton of information to process, it can seem overwhelming; however, if you do your research and take your time and put in a good plan, I’m sure your upgrade will be successful

Helpful links:
VMware Interoperability Guide: http://www.vmware.com/go/interop
VMware Compatibility Guide: http://www.vmware.com/resources/compatibility/search.php
VMware Docs: https://docs.vmware.com/en/VMware-vSphere/index.html 
Guest OS Installation Guide: partnerweb.vmware.com/GOSIG/home.html

Helpful Knowledge Base Articles: ( https://kb.vmware.com/s/ )
Information before upgrading to vSphere 6.5 (2147548)
VMware vSphere Upgrade Policies (2149713)
Update Sequence for vSphere 6.5 and its compatible VMware products (2147289)
Best Practices for upgrading to vCenter Server 6.5 (2147686)
Supported and Deprecated Topologies for VMware vSphere 6.5 (2147672)
vCenter Single Sign-on and PSC High Availability Compatibility Matrix (2112736)