Articles written by Erik Scholten

About
Erik Scholten is the founder of VMGuru.nl and works for Imtech ICT as a Solution Architect creating the most ingenious virtual infrastructures. He has over 15 years experience as a system engineer and consultant and now he specializes in virtualization. His current job includes selling, presenting, designing and developing virtual infrastructures for some major companies in the Netherlands.
In 2009, 2010, 2011 and 2012 VMware awarded him the vExpert award for his virtualization community efforts.
Tuesday, May 14th, 2013, by Erik Scholten
At VMGuru.nl we’ve done a lot of articles on VDI performance and best practices. Recently I’ve done an article on ‘How to improve VMware View video performance‘ and Edwin did an article on ‘Boosting Google maps and video with VMware View‘.
Researching the possibilities and changes with Horizon View 5.2, Eric Sloof pointed me to two new technical white papers.
VMware recently released two white papers, one on the performance and best practices for the new VMware Horizon View 5.2 and the second on the use of hardware accelerated 3D graphics with VMware Horizon View 5.2.
This is must read material for everyone who’s designing, planning and installing a VMware Horizon View 5.2 VDI environment.
(more…)
Tags: Best Practices, Horizon View, VMware
Posted in Best Practices, Infrastructure Design, View, VMware | No Comments »
Tuesday, May 7th, 2013, by Erik Scholten
Every time a vendor releases a new hypervisor, it’s always more reliable and stable than all the previous versions and certainly better than the competition. But was the previous version all that bad?
Of course with the addition of more and more advanced features it becomes more and more difficult to create a reliable and stable product simply because of the immense amount of code and the interdependency between all the different components. VMware has always had a dedicated hypervisor and with the release of ESXi they further reduced the code base of vSphere ESXi to minimize the attack surface. This also reduces the amount of code to patch which further improves reliability, stability and security.
Last week I visited a customer who, much to my surprise, still ran some VMware ESX 2.5 servers. According to the customer the servers ran fine and they had never had any problems.
When we opened the console, we found out that these ancient ESX 2.5 servers have had an amazing availability during the last 4 years.
Check this out!
(more…)
Tags: ESX, VMware
Posted in ESX/ESXi, VMware | 3 Comments »
Friday, April 26th, 2013, by Erik Scholten
As I said earlier this week, VMware memory management is still a topic which a lot of VMware administrators don’t understand.
Tuesday I discussed the virtual machine memory allocation graphs. Today we will deal with VMware vSphere uses transparent page sharing (TPS), memory compression, host swapping and ballooning.
VMware ESXi, a crucial component of VMware vSphere 5.0, is a hypervisor designed to efficiently manage hardware resources including CPU, memory, storage, and network among multiple, concurrent virtual machines. In this article I will describes the basic memory management concepts in VMware ESXi and describe the performance impact of these options.
ESXi uses several innovative techniques to reclaim virtual machine memory, which are:
- Transparent page sharing (TPS)—reclaims memory by removing redundant pages with identical content;
- Ballooning—reclaims memory by artificially increasing the memory pressure inside the guest;
- Hypervisor swapping—reclaims memory by having ESXi directly swap out the virtual machine’s memory;
- Memory compression—reclaims memory by compressing the pages that need to be swapped out.
So how does it work.
(more…)
Tags: memory management, vSphere
Posted in ESX/ESXi, VMware | 1 Comment »
Tuesday, April 23rd, 2013, by Erik Scholten
VMware memory management is still a topic which a lot of VMware administrators don’t understand. I often come across people who have no idea when VMware vSphere uses transparent page sharing (TPS), memory compression, host swapping or ballooning. They even mention disabling or removing the ballooning driver without knowing why. I also meet a lot of VMware administrators having trouble explaining the virtual machine memory allocation graphs.
Let’s start with the last one.
We all know the nice graphs with all different colors, 9 different memory classifications and reservations and limits.
This screen shows the following values:
Host memory
- Consumed memory;
- Overhead consumption;
Guest memory
- Private memory;
- Shared memory;
- Swapped memory;
- Compressed memory;
- Ballooned memory;
- Unaccessed memory;
- Active memory.
(more…)
Tags: memory management, vSphere
Posted in ESX/ESXi, VMware | 2 Comments »
Friday, April 19th, 2013, by Erik Scholten
In 2008 I wrote an article named “Hyper-V, not in my datacenter!” which was based on Hyper-V version 1. In 2009 I wrote an article named “Hyper-V, the laughter continues” and “ESX vs Hyper-V mythbusting myth” which was based on Hyper-V version 2.
Microsoft promised/warned us that with Windows Server 2012 Hyper-V version 3 this would all be history. But as Sander wrote in a more recent article named “Windows Server 2012 Hyper-V: overpromising and underdelivering” this turned out to be a marketing statement based on a premature product with no suitable management tools.
But now with the release of System Center 2012 Service Pack 1, Hyper -V version 3 should be the VMware vSphere-killer (according to MS).
Too bad, the sequel continues! Yesterday Edwin pointed me to a great article by Justin Paul, a fellow blogger, vExpert, VCP and EMC specialist, in which he describes his recent struggles with Windows Server 2012 Hyper-V.
True, in the last four point Justin refers to some information which is a bit outdated, but he has a valid point stating “Then explain why it happened to a 2012 hyperV cluster if it is fixed ?” when people in the comment section claim that Microsoft solved this in the new version of Hyper-V. Apparently they weren’t fixed.
When I read Justin’s comments on the CSV issues and the hassle to setup a Hyper-V environment, I stand by my earlier position, this is not a product which I trust to base my enterprise IT infrastructure on. So still, “Hyper-V? Not in my datacenter…”.
Check out Justin’s article on “Justin’s IT Blog”.
Tags: Hyper-V, Microsoft
Posted in Hyper-V, Microsoft | 1 Comment »
Tuesday, April 16th, 2013, by Erik Scholten
Yesterday I was busy trying some things in my VMware Horizon View 5.2 environment and after a while I got tired of repeating the same tasks on different desktop pools over and over again. Looking for a way to make things easier I came across the View Pool Manager which is a VMware Fling that allows VMware Horizon View administrators to easily manage multiple desktop pools at the same time.
With this tool VMware solves one of the biggest challenges a VMware View administrators faces in large deployments is desktop pool maintenance. Commonly each desktop pool has an Active Directory security group entitlement with the number of users a given desktop pool will support. As employees leave/join the organization, security groups require maintenance to ensure the number of users in each group correctly match the amount of desktops available. VMware View Pool Manager allows VMware View administrators to easily manage users across desktop pools and security groups for large deployments.
This tool allow administrators to bind an Active Directory connection and specify:
- How many users there should exist per group (based on VMware View pool size);
- Floating or Persistent deployment;
- Source Security Groups (all users to be distributed to pools);
- Destination Security Groups (All groups the users may be assigned to).
The View Pool Manager requires .NET Framework 4.0. The .NET 3.5 SP1 installation might require Internet connectivity to download more files. Verify that you are a member of the Administrators group on on the domain.
I tried this tool in my test environment and it’s a great help. It really saved me a lot of time in a small environment, so in a large VMware Horizon View deployment this tool should help the View administrators to save hours of work adding, removing and maintaining users, desktop pools and security groups.
The View Pool Manager is a development from Andre Leibovici (myvirtualcloud.net).
I really like it, so when you have a View environment and need a lot of time maintaining it, give it a try!
Download View Pool Manager.
Tags: View Pool Manager
Posted in View, VMware | Comments Off
Tuesday, March 12th, 2013, by Erik Scholten
Last month we asked to vote for us if you appreciated our blog and apparently a lot of you did.
This year almost 1.300 votes were recorded compared to 1.200 last year, also the total number of blogs on the list increased from 187 to 243 blogs to choose from. There were over 80 new blogs on the ballot and 4 new blogs made it into the top 25. The enormous number of VMware blogs makes it so much tougher to get in the top 25.
So unfortunately we dropped from the 19th to the 31st spot on the list.

Besides that there are tons of bloggers from VMware or VMware/virtualization-related companies which create excellent content, so that a top 25 spot for an independent blogger seems impossible. Luckily Eric created a separate category for that and guess what?
You voted us as 4th Favorite Independant VMware blog! THANK YOU!

As independent bloggers we are very proud and honored that VMGuru.nl finished #4 in this competitive environment. Thanks to Eric Siebert’s for organizing this yearly blogger contest on vSphere-land.com.
We appreciate your votes and ongoing support and want to thank all who voted for us!!!
Tags: Top 25 blogs, Top 50 Blogs, vSphere-land
Posted in VMGuru.nl | Comments Off
Monday, March 4th, 2013, by Erik Scholten
So you want to attend TechEd 2013?
In March, Veeam is giving away a free pass to TechEd 2013. All you have to do is register.
The winner will be selected on March 18, so you have two weeks left to win!

Tags: Veeam
Posted in Third party product(s) | Comments Off
Thursday, February 21st, 2013, by Erik Scholten

Last year VMGuru.nl dropped for the 13th to the 19th spot in the top VMware/virtualization blogs 2012. Now, it is time again to vote the top VMware/virtualization blogs for 2013.
Please help us to reclaim the 13th position or even leap into the top 10!
So if you like our blog please vote VMGuru.nl #1.
As in last years poll you can vote in special categories to help distinguish certain types of blogs. The categories are independent of the general voting so first pick and rank your top 10 overall favorite blogs and then choose your favorite blog in each category.
VMGuru.nl also participates in the Top Independent blog for 2013!
Tags: Top 25 blogs, VMGuru.nl
Posted in VMGuru.nl, VMware | Comments Off
Monday, February 11th, 2013, by Erik Scholten
Today, VMware announced the acquisition of Virsto Software, a company which creates storage optimization software for virtual environments.
Any administrator will tell you that managing performance and data services for virtual machines can be challenging, especially in I/O-intensive environments like virtual desktops. With Virsto storage optimization software you can accelerate I/O performance for any block-based storage system and deliver data efficiency services like snapshots and clones. With these technologies it is possible to improve the performance and utilization of storage systems.
Paired with VMware vSphere, the Virsto storage hypervisor is a simple plug-in that addresses the storage problems associated with server and desktop virtualization. With Virsto enterprises can:
- Reduce VM disk footprint by 90%
- Unclog I/O bottlenecks and triple VM density
- Increase VM performance up to 10x
- Eliminate 99% of the time spent provisioning VM storage
VMware will continue to offer Virsto’s standalone virtual appliance to help accelerate storage performance and improve efficiency in VMware vSphere environments. But their main use for Virsto is to include the Virsto technology into the VMware products and improve their software defined storage solutions and therefor improving their overall software defined datacenter solution.
More information regarding the acquisition can be found here.
Tags: Virsto, VMware
Posted in Third party product(s), VMware | Comments Off
Wednesday, February 6th, 2013, by Erik Scholten
Would like to hear more about Software Defined Datacenters from experts like Frank Denneman, Mike Laverick, Cormac Hogan, Kamau Wanguhu and many others? VMware and IBM are organizing an awesome event in the Benelux. It is a full day event and it is free for everyone, if you just want to sign up… go here. If you need to be convinced keep reading as there are some awesome sessions scheduled.
Schedule
09.00 – 09.30 Registration
09.30 – 09.45 Welcome
09.45 – 10.30 Keynote VMware: Software-Defined Data Center
10.30 – 11.15 Keynote IBM: Converged Systems: beyond NextGen DC’s
11.15 – 11.30 Break and split into parallel sessions
11.30 – 12.15 Parallel track 1 or meet the expert
12.15 – 13.00 Lunch
13.00 – 13.45 Parallel track 2 or meet the expert
14.00 – 14.45 Parallel track 3 or meet the expert
15.00 – 15.45 Parallel track 4 or meet the expert
16.00 – 16.45 Parallel track 5 or meet the expert
16.45 – 17.30 Networking drink
(more…)
Tags: VMware
Posted in Events, VMware | Comments Off
Sunday, February 3rd, 2013, by Erik Scholten

This week Teradici, creator of the PCoIP protocol, released a technology preview of their new product named Teradici Arch. Teradici Arch is asoftware-based solution that enables the use of the PCoIP protocol for Microsoft RDS as an alternative to Microsoft RDP.
This should provide better user experience and access to the entire PCoIP ecosystem, PCoIP thin clients, APEX accelerator cards, etc.
Teradici has been forced to delay the release of Arch due to a scalability issue but a new tech preview will still allow enterprises to familiarize themselves with the product. The final product release is expected in Q3 2013.
This solution should be an ideal solution for enterprises with mixed environment of VMware View VDI and Microsoft RDS. I wonder how many of these mixed environments exist. The only mixed PCoIP/RDP environments I have seen in my work are View environments where both protocols are used to connect to the same View desktops to use MMR instead of PCoIP acceleration.
The PCoIP protocol is now available for use with terminal services for more performance over any network type and access to the PCoIP ecosystem of products including low maintenance, ultra-secure zero clients. Teradici Arch enables customers to:
(more…)
Tags: Microsoft, Teradici, View
Posted in Microsoft, Third party product(s), View | 1 Comment »
Wednesday, January 23rd, 2013, by Erik Scholten
During the last weeks we’ve been busy implementing a large VMware View deployment for one customer and planning an even larger VMware View deployment for another customer. At the first site we ran into some video performance issues which we definitely want to avoid during the second project.
In our quest to solve and avoid the video performance issues we ran into a number of ways to improve the video performance in VMware View that I would like to share.
First of all, we used the information below from the VMware Architecture Planning Guide:
480p-formatted video You can play video at 480p or lower at native resolutions when the View desktop has a single virtual CPU. If the operating system is Windows 7 and you want to play the video in high-definition Flash or in full screen mode, the desktop requires a dual virtual CPU.
720p-formatted video You can play video at 720p at native resolutions if the View desktop has a dual virtual CPU. Performance might be affected if you play videos at 720p in high definition or in full screen mode.
1080p-formatted video If the View desktop has a dual virtual CPU, you can play 1080p formatted video, although the media player might need to be adjusted to a smaller window size.
3D If you plan to use 3D applications such as Windows Aero themes or Google Earth, the Windows 7 View desktop must have virtual hardware version 8 and turn on the pool setting called Windows 7 3D Rendering. Up to 2 monitors are supported, and the maximum screen resolution is 1920 x 1200. This non-hardware accelerated graphics feature enables you to run DirectX 9 and OpenGL 2.1 applications without requiring a physical graphics processing unit.
These are the settings we used to size the first solution, so we use a Windows 7 desktop image with dual vCPU, 2GB memory, a VMXNET3 adapter and hardware version 8.
This is good for playing 720p in native video resolution but when scaling to full screen this setup does not run smoothly.
(more…)
Tags: performance, video, View, VMware
Posted in View, VMware | 2 Comments »
Friday, January 18th, 2013, by Erik Scholten
Last week I got a tip on a new book on VMware vSphere 5 I would like to share. It’s a VMware Press book which is called ‘Building a virtual Datacenter’ and it has been published in 3 different language : English, Spanish and French which is uncommon for a book on VMware.
The book provides an understandable and global view of vSphere 5, with a ton of information and advice from real world examples. It describes the necessary design choices in a way which is accessible to most readers, not only to a select group of experts.
The book has a nice buildup, the first chapters are devoted to understanding VMware vSphere 5’s functionalities and in the following chapters the links between this technology and the datacenter’s various elements are described such as servers, storage, network, backup and service continuity. In the last chapter, a case study of a migration to a virtualized environment within a large company’s datacenter is discussed, with objectives clearly defined by the corporation’s management.
This book is intended primarily for those in charge of infrastructure projects within information systems like system engineers, VMware and storage administrators, project managers, consultants, architects, sales specialists, evangelists etc.
You can find more information on Amazon.
Tags: book, VMware
Posted in VMware | 1 Comment »
Thursday, January 3rd, 2013, by Erik Scholten
Last month the VMGuru-crew has been busy to update our infrastructure to improve the reliability and performance.
Yesterday Alex fixed the last issue so you all can enjoy the new, improved, faster and more reliable VMGuru.
This way we’re ready to present you with the more news, tests, how-to’s and the latest in virtualization.
So from all of us at VMGuru, a very happy new year!
Posted in VMGuru.nl | Comments Off
Wednesday, December 19th, 2012, by Erik Scholten
In December you may become the winner of the ultimate new year’s resolution from Veeam
which includes a Veeam Dream Lab and more!
Enter for a free chance to win – and WIN BIG:
- TWO HP ProLiant ML 310e G8 Servers
- NETGEAR ReadyNAS storage system with 4 SSDs drives
- HP V1410-16G Ethernet switch
- TechNet Plus subscription for 1 year
- Online course, books and test from
VMware Education Services or Microsoft Learning
- …and a MICROSOFT SURFACE!
Tags: Veeam
Posted in Third party product(s) | Comments Off
Wednesday, December 5th, 2012, by Erik Scholten
Back by popular demand, the Enterprise Hypervisor feature comparison.
After the release of our latest comparison I’ve received a lot of requests to include RedHat’s RHEV to the comparison. Although I’ve never encountered it in enterprise environments, I decided to add it as a service to our readers.
I based the RedHat features on their 3.1 version which is in beta right now. This is because I’ve limited knowledge of the product and I received an updated comparison from one of our readers based on this version.
I hope you find the new Enterprise Hypervisor comparison useful and feel free to contact us when you have feedback for us to improve the list.
Tags: Citrix, Hyper-V, Microsoft, RedHat, RHEV, VMware, vSphere, XenServer
Posted in Citrix, Hyper-V, Microsoft, VMware, vSphere, XenServer | 3 Comments »
Wednesday, November 21st, 2012, by Erik Scholten

Last Thursday Cisco released version 1.0 of their new multi-UCS-domain management tool,
UCS Central and now it is generally available.
UCS Central is a product that enables IT administrators to manage multiple UCS domains that are managed through individual UCS Managers from a single location through a single interface. UCS Central works closely with UCS Manager and provides consolidated management functionality for multi-UCS-installations. It uses a policy management framework similar to UCS Manager but provides a broader scope of these policies across multiple UCS domains.
In addition, it also provides consolidation of data such as hardw
are and firmware inventory, faults, ID pools. The product is deployed as a virtual machine that works with the multiple UCS managers. UCS Central manages thousands of physical blade and rack servers that are integrated with UCS fabric interconnects distributed across multiple UCS domains. UCS Central provides a intuitive web based GUI and an accompanying CLI for user access . It also provides an XML API similar to the one found in UCS Manager to provide automation and integration capabilities with higher level systems management tools.
(more…)
Tags: Cisco, UCS
Posted in Cisco | Comments Off