VM /ETC

Posts Tagged ‘planning’

VMware has published a vSphere Pre-requisites Checklist PDF that will be very handy document to have when planning for the upgrade of a current VMware Infrastructure. The following is part of the document’s introduction and explains it’s purpose:

“This Pre-requisites Checklist is intended for those involved in planning, designing, and upgrading an existing VMware Infrastructure to VMware vSphere. The intended audience includes the roles listed below:

• Solution Architects responsible for driving architecture-level decisions
• Consultants, Partners, and IT personnel, who require knowledge for deploying and upgrading the vSphere infrastructure

it is assumed that they have knowledge and familiarity with VMware Infrastructure and have access to the VMware Infrastructure and VMware vSphere product documentation for reference.”

The document is considered a draft version, and will be updated when vSphere is generally available (GA) later this Quarter (Late May?). Even in it’s current state, the PDF walks administrators and architects through all possible planning and upgrade scenarios of both vCenter and ESX  hosts and points out a lot of the potential gotchas of a vSphere 4 migration.

I’m sure I will use this document regularly over then next 12 months. I might as well have it laminated once it’s finalized after GA!

VMware’s simulcast event was about a revolutionary Cloud OS and how Vsphere is a visionary, data center changing software release. Now that it has been officially announced, there are posts everywhere about the features and functionalities of VMware vSphere 4. Those discussions are exciting and true, but I feel the fact that vSphere is simply the latest release of ESX and VMware Virtual Infrastructure (VI) gets lost in the fanfare. I tend to think at the upgrade and implementation level, so this post quickly focuses on how current customers will get their new licenses along with a few changes to consider before upgrading. The Cloud will happen, and there is no doubt that VMware vSphere will be instrumental in that, but for now, VMware customers need to understand what is involved in transitioning existing virtual infrastructure to vSphere 4.

Read the rest of this entry »

“Should I use VMFS or RDMs (Raw Device Mappings) for my VMware ESX virtual machines (VMs)?” It’s a popular discussion not just for new virtual infrastructure (VI) planning but for existing environments as well. In my experience, Many VMware ESX virtual machines using RDMs were created because of a perceived boost in VM and application performance. Somehow, the wrong impression became widespread: the proprietary VMware VMFS file system created too much I/O overhead and slowed down the VM performance. Although the VMFS reputation has been publicly repaired again, there are still regular challenges explaining this virtual disk myth to VMware administrators.

There are definite pros and cons for using both VMFS and RDMs. This post suggests the 3 most common practical reasons (in my opinion) to use RDMs. That is, reasons that benefit VI administrators, leverage a VM’s native operating system,  or take advantage of technologies and process designed for physical environments. I also provide some links to a few other blogs that have recently explored the same RDM vs VMFS topic as supporting examples.

First, if proof is still needed that performance should not be a factor in the VMFS versus RDM decision, check out VMware’s own PDF titled Performance Characteristics of VMFS and RDM.

So what are some practical reason for using RDMs? Read the rest of this entry »

As IT budgets decline, old servers called to virtualization duty is an article written by Alex Barrett and Colin Steele on SeachVirtualization.com. Other then asking some pretty good virtualization sources their opinions , I think the article does a great job explaining why the expense of buying modern hardware still makes sense even in today’s economy. Whether to buy new servers is a common decision being made today as more and more companies are conducting capacity planning studies for consolidation to virtual infrastructure analysis.

Read the entire article for several great points, but here is one quote as an example argument:

“The first thing to determine is whether installing virtualization on older hardware actually saves money. Today’s servers are equipped with quad- and six-core CPUs that can deliver much greater consolidation ratios that single- or dual-core models, he said. “VI3 [VMware Infrastructure 3] is licensed per socket, so you’re paying the same cost for older CPUs but you’re getting less bang for your buck.”

But if the budget for new hardware simply isn’t there, consider the age of a server and how much life it has left in it. When identifying a candidate for a virtualization host, identify a box that is three years or younger and has “had a relatively low runtime,” the systems administrator said.”

I collaborated with Joerg, Stephen, and Martin while writing Planning for Virtual Infrastructure: Avoid the Pitfalls at GestaltIT.com. The post offers many virtual infrastructure planning considerations in the areas of migration, performance, storage, administration, backup / restore, and disaster recovery.

Please go check it out!

I was surprised to discover that the ability to estimate the size needed for the VMware VirtualCenter (VC) database was built in to the VirtualCenter Management Server Configuration options in VC 2.5. This means that the next time you are asked by your DBA “How big a database does VC need?” you can answer that question from the convenience of your VI Client.

Just point the VI Client at your VC 2.5 server and then use the Administration MENU (not the administration button). Select VirtualCenter Management Server Configuration. Then click on Statistics.

Here’s a screen shot from a VI Client pointed at a VC 2.5 Update 3 server. Read the rest of this entry »

If you are considering virtualizing SQL, check out a great post from vm0.blogspot.com. Running SQL Server on ESX makes some great suggestions for planning  CPU, RAM, and Disk I/O to allow for the highest performance possible of your database virtual machines (VM).

The section on disk I/O made me think – specifically about whether creating RDMs to raw disks was really a better choice than carefully planning VMFS LUNs. There is just too much convenience with using VMFS in my opinion, and I’ve never really been convinced that any report or testing has proven RDMs offer better performance than carefully planned VMFS. So, instead of a long comment on the vm0 post I decided to blog about it here at VM /ETC.

Be sure to read the entire post for the RAM and CPU recommendations, but here is the section that inspired me: Read the rest of this entry »