Microsoft

You are currently browsing articles tagged Microsoft.

Technology Short Take #29

Monday, February 4, 2013 in Networking, Security, Storage, Virtualization by slowe | 6 comments

Welcome to Technology Short Take #29! This is another installation in my irregularly-published series of links, thoughts, rants, and raves across various data center-related fields of technology. As always, I hope you find something useful here.

Networking

  • Who out there has played around with Mininet yet? Looks like this is another tool I need to add to my toolbox as I continue to explore networking technologies like OpenFlow, Open vSwitch, and others.
  • William Lam has a recent post on some useful VXLAN commands found in ESXCLI with vSphere 5.1. I’m a CLI fan, so I like this sort of stuff.
  • I still have a lot to learn about OpenFlow and networking, but this article from June of last year (it appears to have been written by Ivan Pepelnjak) discusses some of the potential scalability concerns around early versions of the OpenFlow protocol. In particular, the use of OpenFlow to perform granular per-flow control when there are thousands (or maybe only hundreds) of flows presents a scalability challenge (for now, at least). In my mind, this isn’t an indictment of OpenFlow, but rather an indictment of the way that OpenFlow is being used. I think that’s the point Ivan tried to make as well—it’s the architecture and how OpenFlow is used that makes a difference. (Is that a reasonable summary, Ivan?)
  • Brad Hedlund (who will be my co-worker starting on 2/11) created a great explanation of network virtualization that clearly breaks down the components and explains their purpose and function. Great job, Brad.
  • One of the things I like about Open vSwitch (OVS) is that it is so incredibly versatile. Case in point: here’s a post on using OVS to connect LXC containers running on different hosts via GRE tunnels. Handy!

Servers/Hardware

  • Cisco UCS is pretty cool in that it makes automation of compute hardware easier through such abstractions as server profiles. Now, you can also automate UCS with Chef. I traded a few tweets with some Puppet folks, and they indicated they’re looking at this as well.
  • Speaking of Puppet and hardware, I also saw a mention on Twitter about a Puppet module that will manage the configuration of a NetApp filer. Does anyone have a URL with more information on that?
  • Continuing the thread on configuration management systems running on non-compute hardware (I suppose this shouldn’t be under the “Servers/Hardware” section any longer!), I also found references to running CFEngine on network apliances and running Chef on Arista switches. That’s kind of cool. What kind of coolness would result from even greater integration between an SDN controller and a declarative configuration management tool? Hmmm…

Security

  • Want full-disk encryption in Ubuntu, using AES-XTS-PLAIN64? Here’s a detailed write-up on how to do it.
  • In posts and talks I’ve given about personal productivity, I’ve spoken about the need to minimize “friction,” that unspoken drag that makes certain tasks or workflows more difficult and harder to adopt. Tal Klein has a great post on how friction comes into play with security as well.

Cloud Computing/Cloud Management

  • If you, like me, are constantly on the search for more quality information on OpenStack and its components, then you’ll probably find this post on getting Cinder up and running to be helpful. (I did, at least.)
  • Mirantis—recently the recipient of $10 million in funding from various sources—posted a write-up in late November 2012 on troubleshooting some DNS and DHCP service configuration issues in OpenStack Nova. The post is a bit specific to work Mirantis did in integrating an InfoBlox appliance into OpenStack, but might be useful in other situation as well.
  • I found this article on Packstack, a tool used to transform Fedora 17/18, CentOS 6, or RHEL 6 servers into a working OpenStack deployment (Folsom). It seems to me that lots of people understand that getting an OpenStack cloud up and running is a bit more difficult than it should be, and are therefore focusing efforts on making it easier.
  • DevStack is another proof point of the effort going into make it easier to get OpenStack up and running, although the focus for DevStack is on single-host development environments (typically virtual themselves). Here’s one write-up on DevStack; here’s another one by Cody Bunch, and yet another one by the inimitable Brent Salisbury.

Operating Systems/Applications

  • If you’re interested in learning Puppet, there are a great many resources out there; in fact, I’ve already mentioned many of them in previous posts. I recently came across these Example42 Puppet Tutorials. I haven’t had the chance to review them myself yet, but it looks like they might be a useful resource as well.
  • Speaking of Puppet, the puppet-lint tool is very handy for ensuring that your Puppet manifest syntax is correct and follows the style guidelines. The tool has recently been updated to help fix issues as well. Read here for more information.

Storage

  • Greg Schulz (aka StorageIO) has a couple of VMware storage tips posts you might find useful reading. Part 1 is here, part 2 is here. Enjoy!
  • Amar Kapadia suggests that adding LTFS to Swift might create an offering that could give AWS Glacier a real run for the money.
  • Gluster interests me. Perhaps it shouldn’t, but it does. For example, the idea of hosting VMs on Gluster (similar to the setup described here) seems quite interesting, and the work being done to integrate KVM/QEMU with Gluster also looks promising. If I can ever get my home lab into the right shape, I’m going to do some testing with this. Anyone done anything with Gluster?
  • Erik Smith has a very informative write-up on why FIP snooping is important when using FCoE.
  • Via this post on ten useful OpenStack Swift features, I found this page on how to build the “Swift All in One,” a useful VM for learning all about Swift.

Virtualization

  • There’s no GUI for it, but it’s kind of cool that you can indeed create VM anti-affinity rules in Hyper-V using PowerShell. This is another example of how Hyper-V continues to get more competent. Ignore Microsoft and Hyper-V at your own risk…
  • Frank Denneman takes a quick look at using user-defined NetIOC network resource pools to isolate and protect IP-based storage traffic from within the guest (i.e., using NFS or iSCSI from within the guest OS, not through the VMkernel). Naturally, this technique could be used to “protect” or “enhance” other types of important traffic flows to/from your guest OS instances as well.
  • Andre Leibovici has a brief write-up on the PowerShell module for the Nicira Network Virtualization Platform (NVP). Interesting stuff…
  • This write-up by Falko Timme on using BoxGrinder to create virtual appliances for KVM was interesting. I might have to take a look at BoxGrinder and see what it’s all about.
  • In case you hadn’t heard, OVF 2.0 has been announced/released by the DMTF. Winston Bumpus of VMware’s Office of the CTO has more information in this post. I also found the OVF 2.0 frequently asked questions (FAQs) to be helpful. Of course, the real question is how long it will be before vendors add support for OVF 2.0, and how extensive that support actually is.

And that’s it for this time around! Feel free to share your thoughts, suggestions, clarifications, or corrections in the comments below. I encourage your feedback, and thanks for reading.

Tags: , , , , , , , , , , , , , , ,

Technology Short Take #28

Thursday, January 10, 2013 in Macintosh, Microsoft, Networking, Security, Storage, Virtualization by slowe | 3 comments

Welcome to Technology Short Take #28, the first Technology Short Take for 2013. As always, I hope that you find something useful or informative here. Enjoy!

Networking

  • Ivan Pepelnjak recently wrote a piece titled “Edge and Core OpenFlow (and why MPLS is not NAT)”. It’s an informative piece—Ivan’s stuff is always informative—but what really drew my attention was his mention of a paper by Martin Casado, Teemu Koponen, and others that calls for a combination of MPLS and OpenFlow (and an evolution of OpenFlow into “edge” and “core” versions) to build next-generation networks. I’ve downloaded the paper and intend to review it in more detail. I’d love to hear from any networking experts who’ve read the paper—what are your thoughts?
  • Speaking of Ivan…it also appears that he’s quite pleased with Microsoft’s implementation of NVGRE in Hyper-V. Sounds like some of the other vendors need to get on the ball.
  • Here’s a nice explanation of CloudStack’s physical networking architecture.
  • The first fruits of Brad Hedlund’s decision to join VMware/Nicira have shown up in this joint article by Brad, Bruce Davie, and Martin Casado describing the role of network virutalization in the software-defined data center. (It doesn’t matter how many times I say or write “software-defined data center,” it still feels like a marketing term.) This post is fairly high-level and abstract; I’m looking forward to seeing more detailed and in-depth posts in the future.
  • Art Fewell speculates that the networking industry has “lost our way” and become a “big bag of protocols” in this article. I do agree with one of the final conclusions that Fewell makes in his article: that SDN (a poorly-defined and often over-used term) is the methodology of cloud computing applied to networking. Therefore, SDN is cloud networking. That, in my humble opinion, is a more holistic and useful way of looking at SDN.
  • It appears that the vCloud Connector posts (here and here) that (apparently) incorrectly identify VXLAN as a component/prerequisite of vCloud Connector have yet to be corrected. (Hat tip to Kenneth Hui at VCE.)

Servers/Hardware

Nothing this time around, but I’ll watch for content to include in future posts.

Security

  • Here’s a link to a brief (too brief, in my opinion, but perhaps I’m just being overly critical) post on KVM virtualization security, authored by Dell TechCenter. It provides some good information on securing the libvirt communication channel.

Cloud Computing/Cloud Management

  • Long-time VMware users probably remember Mike DiPetrillo, whose website has now, unfortunately, gone offline. I mention this because I’ve had this article on RabbitMQ AMQP with vCloud Director sitting in my list of “articles to write about” for a while, but some of the images were missing and I couldn’t find a link for the article. I finally found a link to a reprinted version of the article on DZone Enterprise Integration. Perhaps the article will be of some use to someone.
  • Sam Johnston talks about reliability in the cloud with a discussion on the merits of “reliable software” (software designed for failure) vs. “unreliable software” (more traditional software not designed for failure). It’s a good article, but I found the discussion between Sam and Massimo (of VMware) as equally useful.

Operating Systems/Applications

Storage

  • Want some good details on the space-efficient sparse disk format in vSphere 5.1? Andre Leibovici has you covered right here.
  • Read this article for good information from Andre on a potential timeout issue with recomposing desktops and using the View Storage Accelerator (aka context-based read cache, CRBC).
  • Apparently Cormac Hogan, aka @VMwareStorage on Twitter, hasn’t gotten the memo that “best practices” is now outlawed. He should have named this series on NFS with vSphere “NFS Recommended Practices”, but even misnamed as they are, the posts still have useful information. Check out part 1, part 2, and part 3.
  • If you’d like to get a feel for how VMware sees the future of flash storage in vSphere environments, read this.

Virtualization

  • This is a slightly older post, but informative and useful nevertheless. Cormac posted an article on VAAI offloads and KAVG latency when observed in esxtop. The summary of the article is that the commands esxtop is tracking are internal to the ESXi kernel only; therefore, abnormal KAVG values do not represent any sort of problem. (Note there’s also an associated VMware KB article.)
  • More good information from Cormac here on the use of the SunRPC.MaxConnPerIP advanced setting and its impact on NFS mounts and NFS connections.
  • Another slightly older article (from September 2012) is this one from Frank Denneman on how vSphere 5.1 handles parallel Storage vMotion operations.
  • A fellow IT pro contacted me on Twitter to see if I had any idea why some shares on his Windows Server VM weren’t working. As it turns out, the problem is related to hotplug functionality; the OS sees the second drive as “removable” due to hotplug functionality, and therefore shares don’t work. The problem is outlined in a bit more detail here.
  • William Lam outlines how to use new tagging functionality in esxcli in vSphere 5.1 for more comprehensive scripted configurations. The new tagging functionality—if I’m reading William’s write-up correctly—means that you can configure VMkernel interfaces for any of the supported traffic types via esxcli. Neat.
  • Chris Wahl has a nice write-up on the behavior of Network I/O Control with multi-NIC vMotion traffic. It was pointed out in the comments that the behavior Chris describes is documented, but the write-up is still handy, and an important factor to keep in mind in your designs.

I suppose I should end it here, before this “short take” turns into a “long take”! In any case, courteous comments are always welcome, so if you have additional information, clarifications, or corrections to share regarding any of the articles or links in this post, feel free to speak up below.

Tags: , , , , , , , , , , , , ,

Technology Short Take #23

Tuesday, June 12, 2012 in Linux, Microsoft, Networking, Security, Storage, Virtualization by slowe | 5 comments

Welcome to Technology Short Take #23, another collection of links and thoughts related to data center technologies like networking, storage, security, cloud computing, and virtualization. As usual, we have a fairly wide-ranging collection of items this time around. Enjoy!

Networking

  • A couple of days ago I learned that there are a couple open source implementations of LISP (Locator/ID Separation Protocol). There’s OpenLISP, which runs on FreeBSD, and there’s also a project called LISPmob that brings LISP to Linux. From what I can tell, LISPmob appears to be a bit more focused on the endpoint than OpenLISP.
  • In an earlier post on STT, I mentioned that STT’s re-use of the TCP header structure could cause problems with intermediate devices. It looks like someone has figured out how to allow STT through a Cisco ASA firewall; the configuration is here.
  • Jose Barreto posted a nice breakdown of SMB Multichannel, a bandwidth-enhancing feature of SMB 3.0 that will be included in Windows Server 2012. It is, unexpectedly, only supported between two SMB 3.0-capable endpoints (which, at this time, means two Windows Server 2012 hosts). Hopefully additional vendors will adopt SMB 3.0 as a network storage protocol. Just don’t call it CIFS!
  • Reading this article, you might deduce that Ivan really likes overlay/tunneling protocols. I am, of course, far from a networking expert, but I do have to ask: at what point does it become necessary (if ever) to move some of the intelligence “deeper” into the stack? Networking experts everywhere advocate the “complex edge-simple core” design, but does it ever make sense to move certain parts of the edge’s complexity into the core? Do we hamper innovation by insisting that the core always remain simple? As I said, I’m not an expert, so perhaps these are stupid questions.
  • Massimo Re Ferre posted a good article on a typical VXLAN use case. Read this if you’re looking for a more concrete example of how VXLAN could be used in a typical enterprise data center.
  • Bruce Davie of Nicira helps explain the difference between VPNs and network virtualization; this is a nice companion article to his colleague’s post (which Bruce helped to author) on the difference between network virtualization and software-defined networking (SDN).
  • The folks at Nicira also collaborated on this post regarding software overhead of tunneling. The results clearly favor STT (which was designed to take advantage of NIC offloading) over GRE, but the authors do admit that as “GRE awareness” is added to the cards that protocol’s performance will improve.
  • Oh, and while we’re on the topic of SDN…you might have noticed that VMware has taken to using the term “software-defined” to describe many of the services that vSphere (and related products) provide. This includes the use of software-defined networking (SDN) to describe the functionality of vSwitches, distributed vSwitches, vShield, and other features. Personally, I think that the term software-based networking (SBN) is far more applicable than SDN to what VMware does. It is just me?
  • Brad Hedlund wrote this post a few months ago, but I’m just now getting around to commenting about it. The gist of the article—forgive me if I munge it too much, Brad—is that the use of open source software components might dramatically change the shape/way/means in which networking protocols and standards are created and utilized. If two components are communicating over the network via open source components, is some sort of networking standard needed to avoid being “proprietary”? It’s an interesting thought, and goes to show the power of open source on the IT industry. Great post, Brad.
  • One more mention of OpenFlow/SDN: it’s great technology (and I’m excited about the possibilities that it creates), but it’s not a silver bullet for scalability.

Security

  • I came across this interesting post on a security attack based on VMDKs. It’s quite an interesting read, even if the probability of being able to actually leverage this attack vector is fairly low (as I understand it).

Storage

  • Chris Wahl has a good series on NFS with VMware vSphere. You can catch the start of the series here. One comment on the testing he performs in the “Same Subnet” article: if I’m not mistaken, I believe the VMkernel selection is based upon which VMkernel interface is listed in the first routing table entry for the subnet. This is something about which I wrote back in 2008, but I’m glad to see Chris bringing it to light again.
  • George Crump published this article on using DCB to enhance iSCSI. (Note: The article is quite favorable to Dell, and George discloses an affiliation with Dell at the end of the article.) One thing I did want to point out is that—if I recall correctly—the 802.1Qbb standard for Priority Flow Control only defines a single “no drop” class of service (CoS). Normally that CoS is assigned to FCoE traffic, but in an environment without FCoE you could assign it to iSCSI. In an environment with both, that could be a potential problem, as I see it. Feel free to correct me in the comments if my understanding is incorrect.
  • Microsoft is introducing data deduplication in Windows Server 2012, and here is a good post providing an introduction to Microsoft’s deduplication implementation.
  • SANRAD VXL looks interesting—anyone have any experience with it? Or more detailed technical information?
  • I really enjoyed Scott Drummonds’ recent storage performance analysis post. He goes pretty deep into some storage concepts and provides real-world, relevant information and recommendations. Good stuff.

Cloud Computing/Cloud Management

  • After moving CloudStack to the Apache Software Foundation, Citrix published this discourse on “open washing” and provides a set of questions to determine the “openness” of software projects with which you may become involved. While the article is clearly structured to favor Citrix and CloudStack, the underlying point—to understand exactly what “open source” means to your vendors—is valid and worth consideration.
  • Per the AWS blog, you can now export EC2 instances out of Amazon and into another environment, including VMware, Hyper-V, and Xen environments. I guess this kind of puts a dent in the whole “Hotel California” marketing play that some vendors have been using to describe Amazon.
  • Unless you’ve been hiding under a rock for the past few weeks, you’ve most likely heard about Nick Weaver’s Razor project. (If you haven’t heard about it, here’s Nick’s blog post on it.) To help with the adoption/use of Razor, Nick also recently announced an overview of the Razor API.

Virtualization

  • Frank Denneman continues to do a great job writing solid technical articles. The latest article to catch my eye (and I’m sure that I missed some) was this post on combining affinity rule types.
  • This is an interesting post on a vSphere 5 networking bug affecting iSCSI that was fixed in vSphere 5.0 Update 1.
  • Make a note of this VMware KB article regarding UDP traffic on Linux guests using VMXNET3; the workaround today is using E1000 instead.
  • This post is actually over a year old, but I just came across it: Luc Dekens posted a PowerCLI script that allows a user to find the maximum IOPS values over the last 5 minutes for a number of VMs. That’s handy. (BTW, I have fixed the error that kept me from seeing the post when it was first published—I’ve now subscribed to Luc’s blog.)
  • Want to use a Debian server to provide NFS for your VMware environment? Here is some information that might prove helpful.
  • Jeremy Waldrop of Varrow provides some information on creating a custom installation ISO for ESXi 5, Nexus 1000V, and PowerPath/VE. Cool!
  • Cormac Hogan continues to pump out some very useful storage-focused articles on the official VMware vSphere blog. For example, both the VMFS locking article and the article on extending an EagerZeroedThick disk were great posts. I sincerely hope that Cormac keeps up the great work.
  • Thanks to this Project Kronos page, I’ve been able to successfully set up XCP on Ubuntu Server 12.04 LTS. Here’s hoping it gets easier in future releases.
  • Chris Colotti takes on some vCloud Director “challenges”, mostly surrounding vShield Edge and vCloud Director’s reliance on vShield Edge for specific networking configurations. While I do agree with many of Chris’ points, I personally would disagree that using vSphere HA to protect vShield Edge is an acceptable configuration. I was also unable to find any articles that describe how to use vSphere FT to protect the deployed vShield appliances. Can anyone point out one or more of those articles? (Put them in the comments.)
  • Want to use Puppet to automate the deployment of vCenter Server? See here.

I guess it’s time to wrap up now, lest my “short take” get even longer than it already is! Thanks for reading this far, and I hope that I’ve shared something useful with you. Feel free to speak up in the comments if you have questions, thoughts, or clarifications.

Tags: , , , , , , , , , , , , , , , , ,

Technology Short Take #22

Thursday, May 3, 2012 in Microsoft, Networking, Security, Virtualization by slowe | 5 comments

Welcome to Technology Short Take #22! Once again, I find myself without too many articles to share with you this time around. I guess that will make things a bit easier for you, the reader, but it does make me question whether or not I’m “listening” to the right communities. If any readers have suggestions on sources of information to which I should be subscribing or I should be following, I’d love to hear your suggestions.

In any case, let’s get into the meat of it. I hope you find something useful!

Networking

Security

  • I have to agree with Tom Hollingsworth that we often create backdoors by design simply out of our own laziness. I’ve heard it said—in fact I may have used the statement myself—that no amount of security can fix stupidity. That might be a bit strong, but it does apply to the “shortcuts” that we create for ourselves or our customers in our designs.

Servers/Hardware

  • Kevin Houston (who works for Dell) posted an article about a recent test report comparing power usage between Dell blades and Cisco UCS blades. If you’re comparing these two solutions, find a comparable report from Cisco and then draw your own conclusions. (Always get multiple views on a topic like this, because every vendor—and I know because I work for a vendor, too—will spin the report in their favor.)

Virtualization

That’s it for this time around. I hope that you have found something useful here. If anyone has any suggestions for sites/forums they’ve found helpful with data center-focused topics, I’d love for you to add that information in the comments.

Tags: , , , , , , , ,

The OS is Dead, Long Live the OS

Wednesday, March 28, 2012 in Microsoft, Virtualization by slowe | 3 comments

I just finished reading a post on ZDNet titled “Are Hyper-V and App-V the new Windows Servers?” in which the author—Ken Hess—postulates that the rise of virtualization will shape the future of the Microsoft Windows OS such that, in his words:

The Server OS itself is an application. It’s little more than (or hopefully a little less than) Server Core.

The author also advises his readers that they “have to learn a new vocabulary” and that they’ll “deploy services and applications as workloads.”

Does any of this sound familiar to you?

It should. Almost 6 years ago, I was carrying on a blog conversation (with a web site that is now defunct) about the future of the OS. I speculated at that point that the general-purpose OS as we then knew it would be gone within 5 to 10 years. It looks like that prediction might be reasonably accurate. (Sadly, I was horribly wrong about Mac OS X, but everyone’s allowed to be wrong now and then aren’t they?)

It should further sound familiar because almost 5 years ago, Srinivas Krishnamurti of VMware wrote an article describing a new (at the time) concept. This new concept was the idea of a carefully trimmed operating system (OS) instance that served as an application container:

By ripping out the operating system interfaces, functions, and libraries and automatically turning off the unnecessary services that your application does not require, and by tailoring it to the needs of the application, you are now down to a lithe, high performing, secure operating system – Just Enough of the Operating System, that is, or JeOS.

The idea of the server OS as an application container—what Ken suggests in very Microsoft-centric terms in his article—is not a new idea, but it is good to see those outside of the VMware space opening their eyes to the possibilities that a full-blown general purpose OS might not be the best answer anymore. Whether it is Microsoft’s technology or VMware’s technology that drives this innovation is a topic for another post, but it is pretty clear to me that this innovation is already occurring and will continue to occur.

The OS is dead, long live the OS!

<aside>If this is the case—and I believe that it is—what does this portend for massive OS upgrades such as Windows 8 (and Server 2012)?</aside>

Tags: , , , , ,

Why SR-IOV on vSphere?

Monday, March 19, 2012 in Virtualization by slowe | 21 comments

Yesterday I posted an article regarding SR-IOV support in the next release of Hyper-V, and I commented in that article that I hoped VMware added SR-IOV support to vSphere. A couple of readers commented about why I felt SR-IOV support was important, what the use cases might be, and what the potential impacts could be to the vSphere networking environment. Those are all excellent questions, and I wanted to take the time to discuss them in a bit more detail than simply a response to a blog comment.

First, it’s important to point out—and this was stated in John Howard’s original series of posts to which I linked; in particular, this post—that SR-IOV is a PCI standard; therefore, it could potentially be used with any PCI device that supports SR-IOV. While we often discuss this in the networking context, it’s equally applicable in other contexts, including the HBA/CNA space. Maybe it’s just because in my job at EMC I see some interesting things that might never see the light of day (sorry, can’t say any more!), but I could definitely see the use for the ability to have multiple virtual HBAs/CNAs in an ESXi host. Think about the ability to pass an HBA/CNA VF (virtual function) up to a guest operating system on a host, and what sorts of potential advantages that might give you:

  • The ability to zone on a per-VM basis
  • Per-VM (more accurate, per-initiator) visibility into storage traffic and storage trends

Of course, this sort of model is not without drawbacks: in its current incarnation, assigning PCI devices to VMs breaks vMotion. But is that limitation a byproduct of the current way it’s being done, and would SR-IOV help alleviate that potential concern or issue? It sounds like Microsoft has found a way to leverage SR-IOV for NIC assignment without sacrificing live migration support (see John’s latest SR-IOV post). I suspect that bringing SR-IOV awareness into the hypervisor—and potentially into the guest OS via each vendor’s paravirtualized device drivers, aka VMware Tools in a vSphere context—might go a long way to helping address the live migration concerns with direct device assignment. Of course, I’m not a developer or a programmer, so feel free to (courteously!) correct me in the comments.

Are there use cases beyond providing virtual HBAs/CNAs? Here are a couple questions to get you thinking:

  • Could you potentially leverage a single PCI fax board among multiple VMs (clearly you’d have to manage fax board capacity) to virtualize your fax servers?
  • Would the presentation of virtual GPUs to a guest OS eliminate the need for a paravirtualized video driver, and would the lack of a paravirtualized video driver streamline the virtualization layer even more? The same goes for virtual NICs.

I’m not saying that all these things are possible—again, I’m not a developer so I could be way off base—but it seems to me that SR-IOV at least enables us to consider these sorts of options.

Regarding networking, this is where I see a lot of potential for SR-IOV. While VMware’s networking code is highly optimized, the movement of Ethernet switching into hardware on a NIC that supports SR-IOV has got to free up some CPU cycles and virtualization overhead. It also seems to me that putting that Ethernet switching on an SR-IOV NIC and then adding 802.1Qbg (EVB/VEPA) support would be a sweet combination. Mix in a hypervisor-to-NIC control plane for dynamically provisioning SR-IOV VFs and you’ve got a solution where provisioning a VM on a host dynamically creates an SR-IOV VF, attaches it to the VM, and uses EVB to provision a new VLAN on-demand onto that NIC. Is that a “pie in the sky” dream scenario? I’m not so sure that it’s that far off.

What do you think? Please share your thoughts in the comments below. Where applicable, please provide disclosure. For example, I work for EMC, but I speak for myself.

Tags: , , , , ,

SR-IOV Support in the Next Version of Hyper-V

Sunday, March 18, 2012 in Virtualization by slowe | 7 comments

While browsing my list of RSS feeds tonight, I came across a series of articles by John Howard, a senior program manager on the Hyper-V team at Microsoft. The post was one of a series of posts describing SR-IOV support in the next version of Hyper-V, found in Windows “8″. I hadn’t heard that Microsoft was adding SR-IOV support to the next version of Hyper-V, so when I saw that I was surprised. Personally, I think SR-IOV support is a big deal (see the note at the end of this post for why).

If you’re not familiar with SR-IOV, I suggest you read this quick SR-IOV tutorial I published on this site in late 2009.

Here are the links to John’s SR-IOV in Hyper-V posts:

Everything you wanted to know about SR-IOV in Hyper-V, part 1
Everything you wanted to know about SR-IOV in Hyper-V, part 2
Everything you wanted to know about SR-IOV in Hyper-V, part 3
Everything you wanted to know about SR-IOV in Hyper-V, part 4
Everything you wanted to know about SR-IOV in Hyper-V, part 5

It’s great to see Microsoft adding SR-IOV support to Hyper-V; this brings SR-IOV out of the niche Linux market and into a broader, more mainstream market. This also applies some competitive pressure against market leader VMware, who now has to respond in some fashion—either by adding SR-IOV support to their ESXi hypervisor, or by explaining why SR-IOV support isn’t necessary. Personally, I hope that VMware does the former and not the latter.

(By the way, for those of you wondering why SR-IOV is important, there are lots of potential synergies here—in my view, at least—between hardware switching on an SR-IOV NIC and things like software-defined networking.)

Tags: , , , ,

Technology Short Take #19

Tuesday, January 3, 2012 in Networking, Storage, Virtualization by slowe | 5 comments

Welcome to Technology Short Take #19, the first Technology Short Take for 2012. Here’s this year’s first collection of links, articles, and thoughts regarding virtualization, storage, networking, and other data center technology-related topics. I hope you find something useful!

Networking

  • While configuration limits aren’t the most exciting reading, they are important from time to time. Here’s some configuration limits for the UCS 6100 and 6200 series.
  • Understanding the differences—both positive and negative—between the various approaches to solving a particular challenge is a key skill. That’s why I like this article on HP Flex-10 versus NIOC for VDI. The author (Dwayne) weighs the pros and cons of both approaches in helping to shape network traffic for VDI deployments using 10Gb Ethernet.
  • It would appear that my recent VXLAN and OTV connectivity posts (incorrect VXLAN post here, corrected VXLAN post here, and OTV/VXLAN post here) sparked a discussion about whether we really need to concern ourselves with traffic trombones. On one side we have Brad Hedlund speculating that the network should be treated like a large virtual I/O fabric; on the other side we have Greg Ferro countering that we do need to be concerned about the topology of the network. I can see both sides of the argument, but at this stage of the game, I’m inclined to agree more with Greg. In the future (it’s unclear how far in the future) I think that Brad’s points will be more valid, but not right now.
  • This post by Ivan Pepelnjak on VXLAN, IP multicast, OpenFlow, and control planes highlights some of the current limitations with VXLAN and thus reinforces why I think that Brad’s arguments are a bit ahead of their time.
  • A few folks had some write-ups on Embrane Heleos: Greg Ferro, Jason Edelman, Brad Hedlund, Brad Casemore, and Ivan Pepelnjak. My question (and this is spurred in part by some comments by Brad Casemore): is this another Cisco spin-in move?

Servers/Operating Systems/Applications

Storage

Virtualization

And that it’s for this time around; as always, I hope you’ve found something useful here. Courteous comments are always welcome; feel free to speak up below.

Tags: , , , , , , , , , , ,

Technology Short Take #17

Monday, November 28, 2011 in Linux, Macintosh, Microsoft, Networking, Storage, Virtualization by slowe | 1 comment

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 stuff…I 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!

Tags: , , , , , , , , , , , , , ,

Problem with VMXNET3 Driver

Friday, November 25, 2011 in Virtualization by slowe | 10 comments

A colleague on the EMC vSpecialist team (many of you probably know Chris Horn) sent me this information on an issue he’d encountered. Chris wanted me to share the information here in the event that it would help others avoid the time he’s spent troubleshooting this issue.

What Chris has found is that there is a flaw in Windows Server 2008 and Windows 7 that causes “orphaned NICs” when using the VMXNET3 network driver. There appear to be three cases in which this problem appears:

  1. When you deploy an OVF or OVA of Windows Server 2008 or Windows 7
  2. When you clone a VM running Windows Server 2008 or Windows 7 (this also applies to deploying from a template)
  3. When deploying a vApp within vCD that contains Windows Server 2008 or Windows 7 (this can cause quite a bit of chaos)

Up until now, there were two available workarounds that appeared to resolve this issue:

  1. Use the Intel E1000 driver, which doesn’t cause the same problem. However, it’s unclear how well the E1000 performs with 10 Gigabit Ethernet uplinks.
  2. Use a statically assigned MAC address, which of course doesn’t scale very well in large (and/or dynamic) environments. This is also very difficult to do in vCloud Director (apparently even rising to the level of having to hack the vCD database).

It would appear that the behavior Chris describes is captured in this VMware KB article. There is also a hotfix available in this Microsoft KB article; Chris has tested this hotfix and indicates that it does indeed fix the problem. The referenced Microsoft KB article and the referenced VMware KB article also reference this third Microsoft KB article, further leading me to believe that the articles are indeed related to the same underlying issue.

If you are deploying Windows Server 2008 and/or Windows 7-based VMs in your environment, you might want to take a look at the linked VMware KB and Microsoft KB articles to be sure that you don’t run into the same sorts of problems Chris was experiencing.

Thanks Chris!

Tags: , , , , ,

« Older entries