In this article I’m going to focus on the major features of the basic platform including the flagship product, the ESXi 5 hypervisor, and its management counterpart, vCenter Server.
Dealing with new updates from VMware is much like the IT perspective regarding new releases from Microsoft, fervent excitement with a healthy dose of “How are they going to screw this up?” This is just as true when you look at a major platform upgrade such as that of VMware’s vSphere 5 last year. While there were some hiccups early on, update 1 has been out for a couple of months now so we non-early
adopters should now be ready to step up and embrace all the good that 5 has to offer.
ESXi (aka you really don’t need a console)
The headline difference between the vSphere 4.x hypervisors and vSphere 5 is that VMware has chosen to do away with the Linux based console service appliance that has been in ESX from the start. ESXi, which has been available since version 3.5 of the system, is still Linux based, but is designed to be managed completely via the VI client that we’ve all grown to know and love.
That’s not to say there is no Command Line Interface at all. By either installing the vSphere CLI Windows application or enabling the Remote Tech Support Mode on the host and connecting via SSH one can gain remote command line access to the host, but with a greatly limited command list when compared to the full blown Linux version.
For those that were previously familiar with the ESXi command line options the esxcfg, vicfg and various PowerCLI cmdlets have been replaced with an easier to use set prefixed with esxcli. VMware has released a great reference poster for these commands that I recommend you download if you want to get into using the command line to automate your infrastructure.
Storage system updates
As vSphere 5 was going through beta and first being released it was (and still is) a widely held belief that 5 is a storage driven release. While there are other portions of the platform update, the real heavy lifting resides here. In my mind the major change is the release of VMFS 5, the file system on which VMware does it VM storage.
I would think many of us have tried to vMotion a large VM from one datastore to another only to be told that it wasn’t possible because the block size the store was formatted with didn’t support VMs that large. To remedy this VMFS 5 comes with a unified block size, meaning you don’t have to worry about this anymore. Instead, to deal with the problem of storing smaller files but still using large blocks of size VMFS 5 supports what they call subblocks, where a portion of the store is set aside in 8 KB blocks to be used for any files in the datastore smaller than 1 KB. All of this allows for you to have up to 64 Terabytes in a single extent!
VMware vSphere 5 – VMFS 5
Very close behind VMFS 5 as a headline is the evolution of the Distributed Resource Scheduler (DRS) to work for storage too. DRS was a crowning point of ESX 4, allowing for VMs to automatically be moved from host to host as host utilization rises and falls. With Storage DRS if you have a datastore that suddenly finds itself running out of space or having higher than acceptable levels of latency it will simply move some Virtual Machines off to another datastore with better performance metrics.
We’ll cover the rest of what’s new vSphere 5 in Part 2 of this series which would be posted soon.