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The Significance of VMware VSAN

April 14, 2014

VMware announced on March 12, 2014 that its VMware Virtual SAN (VSAN) product was moving out of beta and would be generally available to customers. A much anticipated product, VSAN offers a huge list of features and addresses a number of customer use cases. So what is remarkable about this product, other than that it serves up a bunch of disk storage to systems providing high performance and other benefits?

To better understand, let us take a brief detour into how we have arrived at this point. In the past, disks were directly connected to systems as Direct Attached Storage (DAS), as shown in the diagram below.




This addressed most customer needs but also had several critical limitations. Storage availability was tied to host system availability, and available storage capacity on one host could not be used elsewhere. Data protection needed to be setup and configured manually, or with specialized disk adapters.

In order to resolve these issues, storage moved to the network and storage capacity could now be shared between multiple systems. Specialized storage controllers supported high performance, offered large capacities, supported multiple host platforms, and were highly available. However, more effort was involved with the configuration and setup of these network storage systems.

There are two major types of network storage – Storage Area Network (SAN), and Network Attached Storage (NAS). This classification is based upon whether they serve block storage (SAN) or file storage (NAS). The diagram below shows the various components of a SAN storage system.




A summary of the benefits and limitations of DAS, and the solution provided by the network storage approach is listed below.

Over the past few years, the performance of network storage systems has greatly increased. A number of features have been integrated into the storage controllers making them more intelligent. However, newer systems impose larger demands on performance of network storage systems. The storage based on spinning disks is unable to keep up with requests from host systems. Network storage has become quite expensive as well, since it provides a large feature set with most features being rarely used.

During this time, standard systems and disks kept increasing performance and reducing in price. This has created the need for a simple, inexpensive, and policy-driven storage platform, which is what VSAN represents.

The table below summarizes the benefits and limitations of network storage, and the solution offered by the VSAN platform.

VSAN is a distributed DAS solution implemented on multiple systems, but without the major limitations of DAS and network storage. It is simple and inexpensive, but also available and reliable. There are no islands of storage, and performance and capacity scale together. VSAN software enables all the distributed storage to function as a single logical pool. Storage policies can be seamlessly implemented, and solid state disks effectively mask the latency of spinning disks.

The significance of this technology lies in its parallels to other popular technologies. What are these technologies, and why were they revolutionary? Watch this space for Part 2 of the VSAN technology story.

Ravi_PicRavi Venkatasubbaiah is an IT executive and business leader with 20+ years experience helping companies manage adoption of emerging technologies. Ravi serves on the Board of Directors at VMware User Group, and as a leader of the Silicon Valley VMUG chapter. He enjoys working with entrepreneurs in Silicon Valley and India, and is an advisor on Strategy, Technology, and Operations. He currently lives in San Jose and blogs at

Thanks for the votes!!

April 9, 2014

thanksFor those of you who haven’t paid close attention or are new to the virtualization blog game, Eric Seibert over at sets up voting for the top virtualization blogs each year. It seems like the amount of blogs grows more and more each year as new bloggers join the conversation and start putting out great content. My vDestination blog, which does not come close to competing with the heavy hitters, came in 3 places better this year at #114 out of 320 blogs. I garnered 29 total votes, so I wanted to take this blog post to thank all of you who took the time to vote for my blog! I’m humbled that anyone is reading my blog, I try to put out good content that I think people will read, some super technical stuff, mixed with less technical posts and some fluff every now and again. Also, I’d like to take this blog post to apologize for my lack of blogging this year, it’s been a super busy year with my new job and a very demanding client. I’ve never worked more hours or been more busy with my day job in all 15 years of my employment history. Thanks for sticking around, reading and following me on Twitter.

What’s to come?
I have some really great things happening on my blog going forward from where it is today. I’ve gained a couple great new guest bloggers/contributors who have graciously agreed to join the blog and share their talents/knowledge with the world through First off, my good friend from Costa Rica, Larry Gonzalez has really been working hard on the vLATAM page of vDestination along with Celia Cristaldo. Nick Fritcsh of VMware has been recently posting some good content, as evidenced by his EMC World Discount post! Thanks Nick! I’ve also been building a good relationship with Ravi Venkatasubbaiah and he’s come on board and start writing for vDestination. It’s very exciting to have these bloggers onboard and I’m looking forward to 2014 being our best year yet. We a little late to start but you’ll start seeing a bunch of good content coming down the pipe.

New Look
I’m also excited to announce that I’ll be rolling out a new blog format, feel and look on vDestination here in the very near future. I’ve been chained by hosting on so I’m looking forward to self hosting, thanks to all that have helped me realize I need to self host. The new site will be easier on the eyes, easier to navigate and fully integrated with Facebook, Twitter, Instagram, LinkedIn, Google+ and possibly more social networking sites in an attempt to reach as many readers as possible. I spend time and money on my blog in an effort to share my knowledge with others who might be looking. A good majority of my first few months of virtualization work was spent hopelessly digging through blogs looking for help to get me where I need to be.

Again, a big thanks to all my readers and followers, I appreciate all of your questions and comments, please keep them coming!

Greg W. Stuart

EMC World Discount Code

April 1, 2014

EMC WorldIt’s been a while since I’ve been able to post on vDestination.  For my return, I thought it would be good to giveaway a few EMC World discount codes to the community.  As a member of EMC Elect, I was given three $150 discount codes to EMC World.  In order to win one of the three codes, you need to have already registered or are very close to registering for EMC World.  Second, comment on this post on why you should receive a discount code.  I will select three winners based upon the replies.

Please be aware that you cannot apply this discount code on top of another discount.  If you have already registered for EMC World and received the early-bird discount, using the EMC World discount code that I am giving away will remove the early bird discount along with any gift you received as part of registering early.  Therefore I would not recommend using this discount code if you are already registered and received a discount greater than $150 or a gift.

The contest ends April 3rd.  The discount code expires on April 7th so you’ll only have four short days to complete the registration using the discount code.  Thanks for reading and make sure to leave a comment in order to be registered to win.

Washington DC VMUG: Register, attend, learn!

March 7, 2014

dcvmugIt’s that time again, a new VMUG meeting is upon us. The Washington DC VMUG will be holding a meeting on Wednesday March 12th, 2014 in Tyson’s Corner, VA from 4 to 7pm. That’s only 5 days from today, so don’t wait around, register now. Pay attention to the title of this blog post, “Register, attend, learn!” These are the 3 things you need to do to get the most out of this VMUG meeting, easy right? That’s a pretty broad set of instructions, let’s delve into what’s going down at this upcoming meeting.

The Agenda
This meetings primary theme will be the Software Defined Datacenter or as you have heard it pronounced, SDDC! If you’ve been paying attention at all in the past year, you have most likely heard about or read about SDDC. It’s a super hot topic and one that’s not going to fade anytime soon. What the Cloud is for the end-user and marketing firms, SDDC is for us, the admins, engineers, and architects. Anyone who has spent time in the datacenter, cabling servers and switches, racking and stacking… SDDC excites us. We’ll have an opportunity to hear from VMware‘s Brad Clemmons who will focus on VMware and the SDDC. We’ll also get to hear from Eric Rife from Nexenta, who can speak to Software Defined Storage and how it ties into the SDDC picture.

Here’s the official agenda:

  • Registration, Welcome and Logistics from DC VMUG Leadership
  • Welcome from Venue Host Ashok Nare, CTO, Octo Consulting
  • VMware Presentation – Brad Clemmons, VMware
  • Nexenta Presentation and Demo – Eric Rife, Nexenta
  • Dinner, Ask the Experts Panel, and Door Prize Giveaway.

  • Is It Worth My Time???
    I recognize that I’m extremely biased when it comes to this question… I’m one of the DC VMUG leaders. My answer is simple, it’s ABSOLUTELY worth your time. I’ve noticed that this is probably the quickest 3 hours I’ll spend all year, simply because the presentations are A+ and the networking is golden. You will gain insight into SDDC directly from VMware and Nexenta without all of the marketing fluff you might normally see in a presentation. This is for technology lovers, by technology lovers. If you haven’t attended a VMUG before, this is a great opportunity to start. It’s free to register, there are door prizes to be given away and most importantly you get to network with other people just like you. Did I mention there is free food? Register now.

    How to Set Your XenServer VMs to Auto-Start

    March 4, 2014

    autostartYes, you read that right… this is a post about Citrix XenServer. “What the heck is a VMware fanboy doing writing about Citrix?” That’s a valid question, but I promise there’s a good reason for this Citrix post on a typically VMware centric blog. I’ve recently had to think outside of the box when it comes to virtualization, as my current position as a Sr. Engineer for a federal client has required me to focus on Citrix more than VMware. I came across a weird issue where my entire XenServer would go offline, most likely because of a memory shortage I think, and when it would start back up all the VMs would remain powered off. After reading that, most of you probably knew this was an easy fix, but not for a VMware admin with little Citrix experience. While I had a good idea that we were probably maxing out our memory and it was shutting down the VMs, I still spent a ton of time troubleshooting that possibility instead of first making sure the VMs could stay online or come back up automatically.

    The Fix
    It turns out, this is a pretty easy fix, and one that should probably be configured on any server running XenServer. Now, stay with me, realize that this is a VMware admin making his first attempt at a Citrix related blog post. I thought someone else would find it helpful, so here are the steps.

    1. First you need to log into your XenServer by KVM in the server room or via ssh, I use a Mac, so I just opened up my terminal app and used the command (see the screenshot below):

    2. Next you’ll enter your password at the prompt and it will may ask you if you want to continue if you have an invalid security certificate, otherwise it will give you the XenServer prompt. From this XenServer prompt you will first need to set your XenServer to allow auto-start by typing the command “xe pool-list” which will give you your UUID for your VM pool (see screenshot below).

    3. Now that you have your VM pool UUID (it’s the string of letters/numbers , you’ll want to grab it and use it in the following command, replacing UUID with your actual pool’s UUID, then hit enter.

    4. After you’ve set your XenServer pool to allow auto-start, next you’ll want to select the VMs that you want auto-start enabled on. Now, this part seems silly to me, why isn’t this just an option you can select? Apparently Citrix disabled auto in XenServer 6.x, because it messed with High Availability (HA) and kicked out some weird results during HA procedures. You’ll need to grab the UUID for each VM that you want to enable auto-start on, so start by running the command “xe vm-list” to get a list of all your VMs and their UUIDs. Then you can type the command in the screenshot below to enable auto-start on that VM. Again, remember to replace your VM’s UUID where it says UUID in the command below.

    That’s all you need, your VMs will now automatically start-up in the event that your XenServer powers off inadvertently or there’s a power outage in your server room (both things that have happened to me).

    Disclaimer: This post is mainly applicable for XenServer 6.0, 6.0.2, 6.1.0, 6.2.0

    Get to know Infinio, you’ll be glad you did

    October 30, 2013

    I recently had the pleasure of sitting down for a chat with Peter Smith from Infinio Systems. If you attended VMworld 2013 in San Francisco or Barcelona you surely heard about Infinio and their great tagline, “NAS + Infinio = Faster VMs”. In this podcast, Peter and I discuss Infinio, what it is, how to install it and we even get into a little whiteboarding! Thanks to Infinio and Peter for taking the time out of his busy schedule to give us the run down on Infinio. Enjoy!

    My Favorite Flings: ThinApp Factory

    October 29, 2013

    This is a guest post by vDestination contributor Nick Fritsch
    VMware Flings have been around for quite some time now.  I personally love VMware Flings b/c many of the ideas that result in the creation of a fling are solutions to challenges that I used to deal with myself, both as a VMware Administrator and a Systems Engineer.  My Favorite Flings is an article I’ve been meaning to write for a while now and finally found some free time to sit down and discuss a few of the Flings that are my favorite.

    What’s a Fling?
    First, a little background about Flings.  Flings are ideas that are turned into projects worked on my VMware engineers in their spare time.  Flings are the answer to the question, “wouldn’t it be cool if you could…”  Even better, Flings are free.  Before you go download your favorite fling, be aware that there is no support for Flings so use with caution.

    Now, onto my favorite flings.  The first is ThinApp Factory.  This is a Fling that continues to be updated as new versions of VMware solutions are released.  ThinApp Factory helps automate the creation of ThinApp packages.  For those unfamiliar with ThinApp, ThinApp is VMware’s application virtualization solution.  A ThinApp is a self-contained virtualized application that is portable, agent less and can be executed on any Windows platform.  Furthermore, an application executed from within a ThinApp is isolated.  Do you still need to run Internet Explorer 6 still but want the security benefits of Internet Explorer 10, with ThinApp, you can run both on the same system, independent of each other.  Need to update Adobe Reader across all desktops/laptops in your environment?  Virtualize Adobe Reader using ThinApp and instead of upgrading Adobe Reader X number of times, simply create an Adobe Reader ThinApp package and deploy that ThinApp package to your desktops/laptops.  Sound interesting and want more information, visit the VMware ThinApp webpage here for more information.

    ThinApp Factory makes creating packages a snap
    So how does ThinApp Factory help me create ThinApp packages?  First, ThinApp Factory is a virtual appliance and can easily be deployed within your vSphere environment or within VMware Workstation.  Point ThinApp Factory at your software repository (network share with all your software installation packages [.exe, .msi, .etc] and ThinApp factory will automate the creation of ThinApp packages based upon applications located in your software repository.  Need to customize your installation?  ThinApp Factory includes recipes that allow for customization as well as the saving of repetitive settings within an application.

    Creating ThinApp packages can be time-consuming which causes slow adoption rates for virtualized applications.  Think of the Apple App Store, users want their applications now.  ThinApp Factory helps automate the packaging process allowing for faster and less error-prone packaging of applications.  Want more information?  Visit the VMware blogs page here.  Want to give it a test-drive?  Visit the VMware Flings webpage to download and try ThinApp Factory for yourself.  As always, I would love to hear feedback on your experiences using ThinApp factory, both good and bad.

    About the Autor
    nickNick Fritsch is an Associate Systems Engineer at VMware. He is a VCP5-DCV, VCP5-DT and an inaugural member of the EMC Elect community. Nick is an active member in the community both speaking and assisting at numerous VMUGs, presenting for vBrownbag and is active on Twitter @nfritsch. In his free time, Nick enjoys the outdoors, whether that’s spending time with his two wonderful daughters or on the golf course with fellow vGolfers.


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