Upgrading vSphere can be a disruptive, time-consuming process that requires the complete overhaul of your infrastructure....
In the past, upgrades occurred on a fairly regular basis with minimal impact; however, that cycle's been broken in more recent VMware releases, in part due to issues with single sign-on and confusion over which web client to use. Now, with the release of vSphere 6.5 Update 1, users are once again faced with the decision of whether to upgrade.
There are a few things you need to know about vSphere 6.5 U1 before you make that decision. VMware's made some changes to the hardware compatibility list (HCL) and removed many of the older tiers of server equipment. Although this equipment technically still functions, VMware no longer supports it, so it's inadvisable to use in a production environment. Although vCenter Server 6.5 can still connect to this equipment to manage older hosts, its days are numbered, and you should have a replacement plan ready. Always be sure to check the HCL before you proceed with the latest vSphere upgrade.
VMFS 6 requires patience
VMware has also discontinued third-party virtual switches in the vCenter update. This means you'll need to migrate Cisco Nexus 1000V or IBM/Hewlett Packard Enterprise equivalents to VMware switches and remove third-party switch software, which can be a challenge. Virtual Machine File System (VMFS) 6 -- included in vSphere 6.5 U1 -- is an even bigger challenge. On the surface, VMFS 6 is similar to VMFS 5, except it adds automatic space reclamation. This feature, originally introduced in vSphere 5, has made a comeback and now works as intended. Automatic space reclamation enables vSphere to communicate with the array about which VMs are deleted. It also allows you to thin provision storage frames, which reduces the VM footprint. Although this is a positive addition, it isn't an upgrade; it's a forklift maneuver. You'll need to use Storage vMotion to move VMs off your existing VMFS 5 data store and reformat that data store to VMFS 6.
In order to play this VM shell game, you need additional storage on which to temporarily host those VMs while you clean off your data store; this can be difficult depending on how much capacity and performance you need. Also, depending on how large your VMs are, it can take hours to complete a Storage vMotion migration for just one machine. If you have many large VMs, this process could take days, weeks or even longer.
Hello, new vSphere Client
The vSphere 6.5 U1 vCenter update boosts host and VM capacity, which should keep VMware's enterprise customer base happy. Perhaps the biggest benefit to this vSphere upgrade is the new HTML5 client. According to VMware, this HTML5 client -- known as the vSphere Client -- will allow the user to do most of the things he was able to do with the older Flash client but without the timeouts, crashes and performance issues associated with Flash. Although some might say that a change in client isn't a good enough reason to upgrade an entire enterprise infrastructure component, many administrators familiar with the Flash client would disagree.
VMware rolls vSAN into VUM
VSphere 6.5 U1 also comes with a positive change to vSAN, specifically that vSAN 6.6.1 is now part of vSphere Update Manager (VUM). This change makes life easier for those who want to use a single interface to keep everything up to date and gives the user the ability to schedule and automate the update process. VUM includes both patches and drivers for vSAN, including additional information on your vSAN cluster within the HCL.
The changes made in vSphere 6.5 U1 are incremental but more than welcome. In order to complete this vSphere upgrade, you need to be running at least vSphere 5.5 Update 3b. Although this vSphere upgrade eliminates support for third-party switches, which will likely disappoint some people, VMware vSphere Distributed Switch (VDS) has proven itself to be a worthy replacement for any third-party switch. The benefits provided by the new vSphere Client are also good motivation to make the switch to vSphere 6.5 U1, even if the journey from VMFS 5 to VMFS 6 is long and arduous. Looking forward, vSphere 6.5 U2 will likely continue with the incremental changes, unless the vSphere Client is fully functional in that update.
VSAN 6.6 and 6.6.1 add major improvements
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What new features and updates are in vSphere 6.5?