Technology Short Take #17
Published on 28 Nov 2011 · Filed in Information · 1117 words (estimated 6 minutes to read)Welcome to Technology Short Take #17, another of my irregularly-scheduled collections of various data center technology-related links, thoughts, and comments. Here’s hoping you find something useful!
Networking
-
I think it was J Metz of Cisco that posted this to Twitter, but this is a good reference to the various 10 Gigabit Ethernet modules.
-
I’ve spoken quite a bit about stretched clusters and their potential benefits. For an opposing view—especially regarding the use of stretched clusters as a disaster avoidance solution—check out this article. It’s a nice counterpoint, especially from the perspective of the network.
-
Anyone know anything about sFlow?
-
Here’s a good post on VXLAN that has some useful information. I’d just like to point out that VXLAN is really only intended to address Layer 2 communications “within” a vApp or a collection of VMs (perhaps a single organization’s VMs), and doesn’t do anything to address Layer 3 routing/accessibility for clients (or “consumers”) attempting to connect to those systems. For that, you’ll still need—at least today—technologies like OTV, LISP, and others.
-
A quick thought that I’m still exploring: what’s the impact of OpenFlow on technologies like VXLAN, NVGRE, and others? Does SDN eliminate the need for these technologies? I’d be curious to hear your thoughts.
Servers/Operating Systems
-
If you’ve adopted Mac OS X Lion 10.7, you might have noticed some problems connecting to older servers/NAS devices running AFP (AppleTalk Filing Protocol). This Apple KB article describes a fix. Although I’m running Snow Leopard now, I was running Lion on a new MacBook Pro and I can attest that this fix does work.
-
This Microsoft KB article describes how to extend the Windows Server 2008 evaluation period. I’ve found this useful for Windows Server 2008 instances in the lab that I need for longer 60 days but that I don’t necessarily want to activate (because they are transient).
Storage
-
Jason Boche blogged about a way to remove stubborn hosts from Unisphere. I’ve personally never seen this problem, but it’s nice to know how to address it should it occur.
-
Who would’ve thought that an HDD could serve as a cache for an SSD? Shouldn’t it be the other way around? Normally, that would probably be the case, but as described here there are certain instances and ways in which using an HDD as a cache for an SSD can improve performance.
-
Scott Drummonds wraps up his 3 part series on flash storage in part 3, which contains information on sizing flash storage. If you haven’t been reading this series, I’d recommend giving it a look.
-
Scott also weighs in on the flash as SSD vs. flash on PCIe discussion. I’d have to agree that interfaces are important, and the ability of the industry to successfully leverage flash on the PCIe bus is (today) fairly limited.
-
Henri updated his VNXe blog series with a new post on EFD and RR performance. No real surprises here, although I do have one question for Henri: is that your car in the blog header?
Virtualization
-
Interested in setting up host-only networking on VMware Fusion 4? Here’s a quick guide.
-
Kenneth Bell offers up some quick guidelines on when to deploy MCS versus PVS in a XenDesktop environment. MCS vs. PVS is a topic of some discussion on the vSpecialist mailing list as they have very different IOPs requirements and I/O profiles.
-
Speaking of VDI, Andre Leibovici has two articles that I wanted to point out. First, Andre does a deep dive on Video RAM in VMware View 5 with 3D; this has tons of good information that is useful for a VDI architect. (The note about the extra .VSWP overhead, for example, is priceless.) Andre also has a good piece on VDI and Microsoft Outlook that’s worth reading, laying out the various options for Outlook-related storage. If you want to be good at VDI, Andre is definitely a great resource to follow.
-
Running Linux in your VMware vSphere environment? If you haven’t already, check out Bob Plankers’ Linux Virtual Machine Tuning Guide for some useful tips on tuning Linux in a VM.
-
Seen this page?
-
You’ve probably already heard about Nick Weaver’s new “Uber” tool, a new VM alignment tool called UBERAlign. This tool is designed to address VM alignment, a problem with how guest file systems are formatted within a VMDK. For more information, see Nick’s announcement here.
-
Don’t disable DRS when you’re using vCloud Director. It’s as simple as that. (If you want to know why, read Chris Colotti’s post.)
-
Here’s a couple of great diagrams by Hany Michael on vCloud Director management pods (both public cloud and private cloud management).
-
People automatically assume that “virtualization” means consolidating multiple workloads onto a single physical server. However, virtualization is really just a layer of abstraction, and that layer of abstraction can be used in a variety of ways. I spoke about this in early 2010. This article (written back in March of 2011) by Brad Hedlund picks up on that theme to show another way that virtualization—or, as he calls it, “inverse virtualization”–can be applied to today’s data centers and today’s applications.
-
My discussion on the end of the infrastructure engineer generated some conversations, which is good. One of the responses was by Aaron Sweemer in which he discusses the new (but not new) “data layer” and expresses a need for infrastructure engineers to be aware of this data layer. I’d agree with a general need for all infrastructure engineers to be aware of the layers above them in the stack; I’m just not convinced that we all need to become application developers.
-
Here’s a great post by William Lam on the missing piece to creating your own vSEL cloud. I’ll tell you, William blogs some of the coolest stuffI wish I could dig in as deep as he does in some of this stuff.
-
Here’s a nice look at the use of PowerCLI to help with the automation of DRS rules.
-
One of my projects for the upcoming year is becoming more knowledgeable and conversant with the open source Xen hypervisor and Citrix XenServer. I think that the XenServer Design Handbook is going to be a useful resource for that project.
-
Interested in more information on deploying Oracle databases on vSphere? Michael Webster, aka @vcdxnz001 on Twitter, has a lengthy article with lots of information regarding Oracle on vSphere.
-
This VMware KB article describes how to enable centralized logging for vCloud Director cells. This is particularly important for HA environments, where VMware’s recommended HA strategy involves the use of multiple vCD cells.
I guess I should wrap it up here, before this post gets any longer. Thanks for reading this far, and feel free to speak up in the comments!