How To Guy
Are You Getting Your Money's Worth with vSphere?
I've spoken to a number of organizations that have upgraded to vSphere, and I've seen that many of them haven't enlisted all of the new features.
- By Rick Vanover
I've spoken to a number of organizations that have upgraded to vSphere, and I've seen that many of them haven't enlisted all of the new features. This seems wasteful, even if those features aren't all earthshaking. (For more on vSphere, see Scott Lowe's September 2009 article, "VMware vSphere: Evolutionary or Revolutionary?") These new features are free for the taking, and as VMware customers we should get our money's worth. Seeing vSphere running as though it were VMware Infrastructure 3 (VI3) makes me and others in the virtualization space just shake our heads.
Here's a list of new features-which may not have been utilized during the upgrade-and how they can benefit virtualized infrastructures:
- Thin-Provisioned Disks: This is by far the best opportunity to reclaim some of your infrastructure that was allocated by VI3. Be advised that just because you can fit more virtual machines (VMs) on one datastore, that doesn't necessarily mean you should. If the number of metadata updates (power-on events, storage migration events, deploying a new VM and more) on the volume become too many, performance will suffer. Start with a small sample and then analyze carefully for your requirements, keeping in mind that it's definitely time to rethink any rule that puts a fixed number of VMs per datastore.
- VMXNET3 Adapter: Part of the paravirtualization driver set, the VMXNET3 adapter is a higher-performance interface than the default offerings. Use this on guest VMs as part of the build process. Note that the Fault Tolerant VM feature is not supported with the VMXNET3 interface.
- Paravirtualized SCSI Adapter: If the VMXNET3 adapter is giving us higher performance, why not get the same from the virtual disk controller? This additional non-default configuration gives high throughput on VMs-to-disk resources.
- vNetwork Distributed Switch: This doesn't have to just be the Cisco Nexus 1000V. The standard distributed switch allows you to make an infrastructure-based networking configuration that's much more robust than any solution simply using standard virtual switches and port groups. My practice is to put guest VM networking on the new distributed switch, and keep a standard virtual switch for management interfaces, such as service consoles.
- Improved Alerting: The alerting engine of vSphere is much improved over the VI3 offering. Gone are the days of getting crafty with the VI Toolkit for basic monitoring tasks such as determining if a Virtual Machine File System (VMFS) datastore is becoming full.
- Hot-Add Virtual Hardware: For operating systems that support this feature, it's worth knowing what to do when you need to assign more resources. Adding CPU, memory and disk to a VM's inventory can get you out of a jam, but you must be careful about leaving the additional resources assigned if the need will not be permanent.
- vSphere Permissions Model: Each object in vSphere can have permissions assigned. This includes clusters, hosts, resource pools, folders, datastores, networks and virtually everything in the vSphere Client. Wouldn't it be nice to delegate more out to application owners, computer operators or others for self-service? I don't know about you, but being paged at 2 a.m. to map a CD-ROM drive can get old quickly.
In my opinion, you must take all the new features forward as part of your upgrade. There will be downtime required to configure the VM-specific features, but the good news is virtualization is the friendliest infrastructure technology I've ever seen, so reconfiguring VMs and the vSphere installation can easily take a vCenter configuration from passable to great.
After all, the features are why we use VMware-based virtualization, right? So what are you waiting for?
Rick Vanover (Cisco Champion, Microsoft MVP, VMware vExpert) is based in Columbus, Ohio. Vanover's experience includes systems administration and IT management, with virtualization, cloud and storage technologies being the central theme of his career recently. Follow him on Twitter @RickVanover.