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Top 5 Planet V12n blog posts week 08

Creating a top 5 seems to be getting more difficult week after week. Not only does the quality of the blog articles increase, the amount of blogs listed on PlanetV12n and the amount of articles also increase steadily. I hope I can keep up with you guys, or I might just need to get a cute assistant to help me out with this…. Hmmm, that's actually not a bad idea. Anyway, here's the list!

  • Eric Gray – Taking snapshots of VMware ESX 4 running in a VM
    Clearly, the capability introduced with VMware vSphere 4 that allows VMware ESX 4 to virtualize itself is a real crowd-pleaser.
    However, one limitation that some have discovered while using this lab-testing technique is the lack of ability to use snapshots with virtual ESX systems. In fact, after taking a snapshot of a virtual ESX VM, you will see the system boot into the recovery shell.
  • Kenneth van Ditmarsch – Using LeftHand Snapshot techniques within a VMware Environment
    Well, currently no integration exists between the LeftHand Snapshot
    technique and vCenter. If the LeftHand Snapshot process is started, vCenter isn’t alerted to quiesce the VM’s and therefore the VM’s are able to continue processing while a LeftHand
    Snapshot is made, which leads to inconsistent VM states. Last year the LeftHand roadmap indicated that vCenter application integration would be available in the new SAN/iQ 8.5. SAN/iQ 8.5 is currently shipped with the HP/LeftHand P4000 G2 nodes and will be available for download on 29th of March for existing P4000 user. For some reasons however vCenter application integration is shoved back to Q4 2010 or later.
  • Steve Kaplan – The multi-hypervisor fallacy
    Implicit in multi-hypervisor advocacy is an undertone of virtualizing
    servers rather than the data center. This myopic perspective
    limits both savings and synergies. Cisco studies, for example, show a
    lack of vNetwork capability results in 30% fewer servers that can be
    virtualized along with 30% higher administrative requirements. Network
    administrators have no way to monitor traffic over a vSwitch for
    compliance, auditing and troubleshooting purposes, and they cannot
    apply network and security policies that follow a VM as it
    live-migrates. Since only vSphere enables vNetwork capabilities,
    multiple hypervisors leave at least a portion of the data center
    running less efficiently and less secure.
  • Steve Chambers – IT Departments and the Collapse of the Silos
    Today I had the opportunity to present at the National Computing Center Think Tank. The NCC have a fantastic remit to bring together practitioners from the private and public sector to explore the current realities. Add to this the vendor invitations where folks like me can share our observations with no axe to sell, and it makes for a really great discussion. Awesome stuff. Prior to this invitation I prepared two documents. First I wrote a blunt paper based on my observations and feedback via Twitter. Second I wrote a Prezi for that to share the findings in ten pieces.
  • Craig Risinger – The Resource Pool Priority-Pie Paradox
    We run into this on a daily basis; Misunderstanding of the “shares”
    concept in combination with resource pools. To start with a bold
    statement: A few VMs in a Low-shares Resource Pool can outperform each
    of many VMs in a High-shares Resource Pool. How is this possible you
    might ask. Resources are divided at the Resource Pool level first. Each
    Resource Pool is like a pie whose size determines amount of resources
    usable (during contention). Then that pie is subdivided among the VMs
    in the pool. A Resource Pool applies to all its VMs collectively. Thus
    a smaller pie divided among fewer VMs can yield more resources per VM
    than a larger pie divided by even more VMs.
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Duncan Epping

About Duncan Epping

Duncan Epping is Principal Architect at VMware (R&D, Integration Engineering) and is focused on vCloud / vSphere architecture and integration. He was among the first VMware certified design experts (VCDX 007). He is the co-author of several books, including best seller vSphere 5.1 Clustering Technical Deepdive. He is the owner and main author of the leading virtualization blog yellow-bricks.com.