From Enterprise Datacenter to Private Cloud, Part 2
Last week, I talked about what it takes to transform an enterprise datacenter to a private cloud. This time, let's focus a bit on the essential first step of preparing for a private cloud.
In order to reach a true private cloud, an organization has got to overcome the barriers of server virtualization and tackle the most challenging of physical servers yet to be virtualized. A good private cloud strategy would be to start with a cloud readiness or fit assessment. This assessment, while broad and detailed, will also include the level at which you are virtualized -- and you'll want to be at 100 percent, if possible.
To achieve 100 percent readiness, let's start with virtualizing tier-1 applications. It is important that we tackle tier-1 apps and this requires advanced understanding of how server virtualization works and the inherent best practices to squeeze every little ounce of performance out of it. There should be no reason to not be able to virtualize Exchange, SQL, SharePoint or other applications of the same caliber. Here's some guidance here as to what to look for from a technical perspective in order to boost performance of these applications:
- Make sure you are using the best combination of virtual hardware for your VMs. For instance, with vSphere, you'll always use the VMXNET3 virtual NIC, and understand the IO requirements of your application. Also, research when to use the VMware PVSCSI adapter as opposed to the default.
- If you are using Hyper-V or XenServer, understand the limitations of the parent partition or the control domain (DOM0) and when to add more resources to it, as all network and storage IO traffic in Hyper-V and XenServer pass through the parent partition or Dom0.
- You should be very familiar with the fact that adding a second virtual SCSI controller and attaching that to a dedicated virtual disk will increase performance and throughput.
- Understand when to use a Raw Device Mapping and in what format.
This is just a sample of things to look at; your service provider or system integrator performing your cloud fit assessment should be able to look at these and more and determine what is preventing you from virtualizing these servers.
Once you've virtualized tier-1 applications, you can then move on to building a meaningful service catalog for users. What I mean by meaningful is having the ability to deliver a service that meets their performance expectations and puts you in a position to charge them for it. Mastering the performance of these applications is a critical cornerstone to a service catalog, which is essential for private clouds.
Service catalogs will consist of building multiple VMs that are considered a service. For instance, if a users wants application X and we have determined that application X is made up of a Web server, a SQL server and a file server, we don't build three servers and give it to the requestor. Instead, that user can log c to our self-service portal and request "Service X," which consists of the necessary requirements. We get away from building VMs to building a collection of VMs that constitute a service and are managed as a single entity.
I want to hear from you on applications you are having a hard time virtualizing and what are the steps you have taken to overcome these issues. Let's try to share some experiences here.
In the next few weeks, I'll tackle cloud infrastructure, automation and orchestration, chargeback and showback, in addition to SLAs and SLEs.
Posted by Elias Khnaser on 02/08/2012 at 12:49 PM