It is pretty common to find Xen products running on top of VMware as the primary hypervisor. I would like to spark a contributed list of housekeeping items for Xen products on top of VMware. Of course we would like the two products to work peacefully like a Xen garden, but this is not always the case.
I would like to bring to your attention to the orphaned VMDK issue with XenDesktop 5.6 FP1 using personal vdisk. Provisioning and deprovisioning desktops is a breeze when using MCS (machine creation services from the DDC) and PVS (provisioning services) over PXE boot. This deprovisioning process does create orphaned VMDK files in VMware. When using the personal vdisk option to build a desktop you end up with 2 separate disks, the identity disk and the pvdisk. When you go through the machine deprovisioning process (deleting), Citrix knows to delete the virtual machine. But, the _pvdisk.vmdk file is left behind. Maybe this is by design so that you can retrieve a user’s personal vdisk later. It is an orphaned VMDK file that gets left behind and is taking up valuable storage. You can either migrate these files to cold storage or delete them. Just be aware that they are sitting there. I like to use Quest PowerGUI with vSphere best practices plugin to search for orphaned VMDK files on a regular basis.
Let’s keep this rolling with other house keeping suggestions.
Since the dawn of virtualization, virtual provisioning has been a great cost saver and a means to reduced IT overhead. Building an internal cloud in the company datacenter meant that we could reduce head count in the IT operations department. If I had 1,000 physical servers in my datacenter, that means I would need at least two staff members in my IT operations department to take care of hardware failures, maintenance and provisioning. If I virtualized those same 1,000 servers into two blade enclosures with five blades in each enclosure I may only need one IT operations staff member. Or I may not even need a staff member at all on the IT operations side, why not just pay for services from the hardware vendor or datacenter to replace that person all together.
Virtualization has always been an easy business justification. The cost savings just cannot be ignored with staff reductions, ease of provisioning, hardware foot prints, power savings, the list goes on and on. The private cloud has existed for many years now. The public cloud has existed for even less time. Over the past 10 years I have seen a great speed in adoption to the private cloud. But for the public cloud there has been much resistance.
Is the resistance to the public cloud futile? Many IT departments see the public cloud as this Borg cube assimilating all the tier 1 applications in the infrastructure, taking jobs with it. It seems today, it’s either adopt to service the cloud or go to an environment where policy dictates that the IT infrastructure cannot exist in the public cloud (for now). This may be due to HIPAA or some other regulation. You will find today that most of the public cloud providers are addressing these concerns by becoming compliant with many of the regulations that stopped businesses before. Once those sales guys get a hook in the IT manager or CIO, there may be no stopping the public cloud assimilation at that point.
Not all public clouds are bad. I think they can be an great integration point for a merged private and public cloud infrastructure. It would also be a great tool for DR. But if the exchange administrator sees his job going out the window because the email environment is being shipped out to a 3rd party hosted email systems, you may see that staff members resume out on the job boards pretty quick. The same goes for VMware administrators. If the company decides to go all public cloud and the datacenter is now in charge of provisioning, there would not be much use for the VMware administrator with managed services in a hosted datacenter.
The point here is that IT has created this great job industry that is still evolving. As the infrastructure evolves, look to the future cost savings for the business and think of how it lines up for your career. Don’t assume that CEO’s, CIO’s or any management will not consider that flexibility and cost savings of a public cloud provider. You will not be able to get away with using outdated hardware or Windows 2000 forever. Prepare to be assimilated into the IT infrastructure future plans which many include some form of public cloud or hop in the DeLorean and head back to 1985 for an IT job.