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.
