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It was one of those weeks again. I had a lot to do, and there is still a lot left to do. I just finished this top 5 and the quality of the articles is again very high. Especially Chad's article, wow… Anyway, start reading and enjoy. This is my gift to all fathers out there.

  • Mike Laspina – Automating vSphere ESX4 Host Installations
    The custom VMware kernel incorporates Linux kickstart scripting
    functionality to invoke automated installations. The script location is
    defined as part of the Syslinux functionality and is available as a
    menu at boot time. A control file located on the boot media provides
    these variable control elements. Depending on the media type Syslinux
    uses a respective cfg file to implement this function. The various
    available Syslinux boot methods that I am aware of are USB, CD, DVD,
    PXE and gPXE. In this blog I will demonstrate an ISO CDROM method to
    perform the automated boot cycle. Any of the boot methods mentioned
    will all work and have varying levels of complexity to achieve.
  • Chad Sakac – VMware I/O queues, “micro-bursting”, and multipathing
    A shallow queue somewhere in the IO path (or an overflowing port
    buffer) will cause the I/O to back off.    You need the queues to be
    deep enough to withstand the bursts – sometimes increasing the queue
    depth is important.   Now, if the problem isn’t actually the bursts,
    but the I/O service time not being sufficient for the sustained
    workload (aka you have a slow, or underconfigured array), increasing
    the queue depth will help for only a fraction of a second, after which
    the deeper queue will still fill up, and now you just have increased the latency even more.
  • Bouke Groenescheij – Queue Depth and more
    Last few weeks we have had some issues regarding our HDS USP-V. For
    some reason a SCSI lock locked the whole VMFS and all ESX servers in
    that cluster were not able to read/write to the VMFS anymore. The LUN
    was still available, however the VMFS not. So this crashed all the VMs
    in the cluster. The incident repeated itself after 6 weeks, on another
    server, other chassis, other switches and so we contacted VMware and
    HDS to help us in this situation.
  • Duncan Epping – VCDX Defense, the blog article
    The last part of the VCDX certification is the defense. In short:
    you will need to write a design, fill out the application and defend
    your design during a two to three hour session. Although I can describe it in 30 words it is not as simple as it may
    sound. First of all your design needs to meet specific requirements. I
    can’t go in to the details unfortunately but when you receive an
    invitation you will receive all the prerequisites. Like me, most of you
    done numerous designs, but keep in mind it needs to be in English and
    so will your defense need to be. This is an extra barrier for many of
    the non- native speakers; I know it was for me.
  • Rodney Haywood – VMware vShield
    You can think of vShield as providing firewalls inside your ESX hosts. Each host runs one or more vShields
    which is a VM (provided as an OVF) which acts as a bridge between the
    real network and your Virtual Machines. These numerous vShield machines
    are all managed by a central vShield Manager (also provided as an OVF, one per vCenter Server). The
    vShield creates two zones, one protected and the other unprotected. The
    traffic enters the protected zone from the unprotected zone. As it
    crosses the zones the vShield performs traffic analysis, discovery and
    stateful firewall protection.