This category contains posts with a security focus or security-related content.
Welcome to Technology Short Take #44, the latest in my irregularly-published series of articles, links, ideas, and thoughts about various data center-related technologies. Enjoy!
- One of the original problems with the VXLAN IETF specification was that it (deliberately) didn’t include any control plane information; as a result, the process of mapping MAC addresses to VTEPs (VXLAN Tunnel Endpoints) wasn’t defined, and the early implementations relied on multicast to handle this issue. To help resolve this issue, Cumulus Networks (and possibly Metacloud, I’m not sure of their involvement yet) has release an open source project called vxfld. As described in this Metacloud blog post, vxfld is designed to “handle VXLAN traffic from any operationg system or hardware platform that adheres to the IETF Internet-Draft for VXLAN”.
- Nir Yechiel recently posted part 1 of a discussion on the need for network overlays. This first post is more of a discussion of why VLANs and VLAN-based derivatives aren’t sufficient, and why we should be looking to routing (layer 3) constructs instead. I’m looking forward to part 2 of the series.
- One ongoing discussion in the network industry these days—or so it seems—is the discussion about the interaction between network overlays and the underlying transport network. Some argue that tight integration is required; others point to streaming video services and VoIP running across the Internet and insist that no integration or interaction is needed. In this post, Scott Jensen argues in favor of the former—that SDN solutions shouldn’t just manage network overlays, but should also manage the configuration of the physical transport network as well. I’d love to hear from more networking pros (please disclose company affiliations) about their thoughts on this matter.
- I like the distinction made here between network automation and SDN.
- Need to get a better grasp on OpenFlow? Check out OpenFlow basics and OpenFlow deep-dive.
- Here’s a write-up on connecting Docker containers using VXLAN. I think there’s a great deal of promise for OVS in containerized environments, but what’s needed is better/tighter integration between OVS and container solutions like Docker.
- Is Intel having second thoughts about software-defined infrastructure? That’s the core question in this blog post, which explores the future of Intel in a software-defined world and the increasing interest in non-x86 platforms like ARM.
- On the flip side, proponents who claim that platforms like ARM and others are necessary in order to move forward with SDN and NFV initiatives should probably read this article on 80 Gbps performance from an off-the-shelf x86 server. Impressive.
- It’s nice to see that work on OpenStack Barbican is progressing nicely; see this article for a quick overview of the project and an update on the status.
Cloud Computing/Cloud Management
- SDN Central has a nice write-up on the need for open efforts in the policy space, which includes the Congress project.
- The use of public cloud offerings as disaster recovery targets is on the rise; note this article from Microsoft on how to migrate on-premises workloads to Azure using Azure Site Recovery. VMware has a similar offering via the VMware vCloud Hybrid Service recovery-as-a-service offering.
- The folks at eNovance have a write-up on multi-tenant Docker with OpenStack Heat. It’s an interesting write-up, but not for the faint of heart—to make their example work, you’ll need the latest builds of Heat and the Docker plugin (it doesn’t work with the stable branch of Heat).
- Preston Bannister took a look at cloud application backup in OpenStack. His observations are, I think, rational and fair, and I’m glad to see someone paying attention to this topic (which, thus far, I think has been somewhat ignored).
- Interested in Docker and Kubernetes on Azure? See here and here for more details.
- This article takes a look at Heat-Translator, an effort designed to provide some interoperability between TOSCA and OpenStack HOT documents for application deployment and orchestration. The portability of orchestration resources is one of several aspects you’ll want to examine as you progress down the route of fully embracing a cloud computing operational model.
- Running Hyper-V with Linux VMs? Ben Armstrong details what versions of Linux support the various Hyper-V features in this post.
- Here’s a quick write-up on running VMs with VirtualBox 4.3 on a headless Ubuntu 14.04 LTS server.
- Nested OS X guest on top of nested ESXi on top of VMware Fusion? Must be something William Lam’s tried. Go have a look at his write-up.
- Here’s a quick update on Nova-Docker, the effort in OpenStack to allow users to deploy Docker containers via Nova. I’m not yet convinced that treating Docker as a hypervisor in Nova is the right path, but we’ll see how things develop.
- This post is a nice write-up on the different ways to connect a Docker container to a local network.
- Weren’t able to attend VMworld US in San Francisco last week? No worries. If you have access to the recorded VMworld sessions, check out Jason Boche’s list of the top 10 sessions for a priority list of what recordings to check out. Or need a recap of the week? See here (one of many recap posts, I’m sure).
That’s it this time around; hopefully I was able to include something useful for you. As always, all courteous comments are welcome, so feel free to speak up in the comments. In particular, if there is a technology area that I’m not covering (or not covering well), please let me know—and suggestions for more content sources are certainly welcome!
Tags: Automation, Docker, Hardware, HyperV, Linux, Networking, OpenFlow, OpenStack, Puppet, Security, Storage, Virtualization, VXLAN, Windows
Welcome to Technology Short Take #43, another episode in my irregularly-published series of articles, links, and thoughts from around the web, focusing on data center technologies like networking, virtualization, storage, and cloud computing. Here’s hoping you find something useful.
- Jason Edelman recently took a look at Docker networking. While Docker is receiving a great deal of attention, I have to say that I feel Docker networking is a key area that hasn’t received the amount of attention that it probably needs. It would be great to see Docker get support for connecting containers directly to Open vSwitch (OVS), which is generally considered the de facto standard for networking on Linux hosts.
- Ivan Pepelnjak asks the question, “Is OpenFlow the best tool for overlay virtual networks?” While so many folks see OpenFlow as the answer regardless of the question, Ivan takes a solid look at whether there are better ways of building overlay virtual networks. I especially liked one of the last statements in Ivan’s post: “Wouldn’t it be better to keep things simple instead of introducing yet-another less-than-perfect abstraction layer?”
- Ed Henry tackles the idea of abstraction vs. automation in a fairly recent post. It’s funny—I think Ed’s post might actually be a response to a Twitter discussion that I started about the value of the abstractions that are being implemented in Group-based Policy (GBP) in OpenStack Neutron. Specifically, I was asking if there was value in creating an entirely new set of abstractions when it seemed like automation might be a better approach. Regardless, Ed’s post is a good one—the decision isn’t about one versus the other, but rather recognizing, in Ed’s words, “abstraction will ultimately lead to easier automation.” I’d agree with that, with one change: the right abstraction will lead to easier automation.
- Jason Horn provides an example of how to script NSX security groups.
- Interested in setting up overlays using Open vSwitch (OVS)? Then check out this article from the ever-helpful Brent Salisbury on setting up overlays on OVS.
- Another series on VMware NSX has popped up, this time from Jon Langemak. Only two posts so far (but very thorough posts), one on setting up VMware NSX and another on logical networking with VMware NSX.
Nothing this time around, but I’ll keep my eyes open for more content to include next time.
- Someone mentioned I should consider using
pfctl and its ability to automatically block remote hosts exceeding certain connection rate limits. See here for details.
- Bromium published some details on a Android security flaw that’s worth reviewing.
Cloud Computing/Cloud Management
- Want to add some Docker to your vCAC environment? This post provides more details on how it is done. Kind of cool, if you ask me.
- I am rapidly being pulled “higher” up the stack to look at tools and systems for working with distributed applications across clusters of servers. You can expect to see some content here soon on topics like fleet, Kubernetes, Mesos, and others. Hang on tight, this will be an interesting ride!
- A fact that I think is sometimes overlooked when discussing Docker is access to the Docker daemon (which, by default, is accessible only via UNIX socket—and therefore accessible locally only). This post by Adam Stankiewicz tackles configuring remote TLS access to Docker, which addresses that problem.
- CoreOS is a pretty cool project that takes a new look at how Linux distributions should be constructed. I’m kind of bullish on CoreOS, though I haven’t had nearly the time I’d like to work with it. There’s a lot of potential, but also some gotchas (especially right now, before a stable product has been released). The fact that CoreOS takes a new approach to things means that you might need to look at things a bit differently than you had in the past; this post tackles one such item (pushing logs to a remote destination).
- Speaking of CoreOS: here’s how to test drive CoreOS from your Mac.
- I think I may have mentioned this before; if so, I apologize. It seems like a lot of folks are saying that Docker eliminates the need for configuration management tools like Puppet or Chef. Perhaps (or perhaps not), but in the event you need or want to combine Puppet with Docker, a good place to start is this article by James Turnbull (formerly of Puppet, now with Docker) on building Puppet-based applications inside Docker.
- Here’s a tutorial for running Docker on CloudSigma.
- It’s interesting to watch the storage industry go through the same sort of discussion around what “software-defined” means as the networking industry has gone through (or, depending on your perspective, is still going through). A few articles highlight this discussion: this one by John Griffith (Project Technical Lead [PTL] for OpenStack Cinder), this response by Chad Sakac, this response by the late Jim Ruddy, this reply by Kenneth Hui, and finally John’s response in part 2.
- The ability to run nested hypervisors is the primary reason I still use VMware Fusion on my laptop instead of switching to VirtualBox. In this post Cody Bunch talks about how to use Vagrant to configure nested KVM on VMware Fusion for using things like DevStack.
- A few different folks in the VMware space have pointed out the VMware OS Optimization Tool, a tool designed to help optimize Windows 7/8/2008/2012 systems for use with VMware Horizon View. Might be worth checking out.
- The VMware PowerCLI blog has a nice three part series on working with Customization Specifications in PowerCLI (part 1, part 2, and part 3).
- Jason Boche has a great collection of information regarding vSphere HA and PDL. Definitely be sure to give this a look.
That’s it for this time around. Feel free to speak up in the comments and share any thoughts, clarifications, corrections, or other ideas. Thanks for reading!
Tags: Automation, BSD, Docker, Fusion, KVM, Linux, Networking, NSX, OpenFlow, OpenStack, OVS, Puppet
Welcome to Technology Short Take #42, another installation in my ongoing series of irregularly published collections of news, items, thoughts, rants, raves, and tidbits from around the Internet, with a focus on data center-related technologies. Here’s hoping you find something useful!
- Anthony Burke’s series on VMware NSX continues with part 5.
- Aaron Rosen, a Neutron contributor, recently published a post about a Neutron extension called Allowed-Address-Pairs and how you can use it to create high availability instances using VRRP (via keepalived). Very cool stuff, in my opinion.
- Bob McCouch has a post over at Network Computing (where I’ve recently started blogging as well—see my first post) discussing his view on how software-defined networking (SDN) will trickle down to small and mid-sized businesses. He makes comparisons among server virtualization, 10 Gigabit Ethernet, and SDN, and feels that in order for SDN to really hit this market it needs to be “not a user-facing feature, but rather a means to an end” (his words). I tend to agree—focusing on SDN is focusing on the mechanism, rather than focusing on the problems the mechanism can address.
- Want or need to use multiple external networks in your OpenStack deployment? Lars Kellogg-Stedman shows you how in this post on multiple external networks with a single L3 agent.
- There was some noise this past week about Cisco UCS moving into the top x86 blade server spot for North America in Q1 2014. Kevin Houston takes a moment to explore some ideas why Cisco was so successful in this post. I agree that Cisco had some innovative ideas in UCS—integrated management and server profiles come to mind—but my biggest beef with UCS right now is that it is still primarily a north/south (server-to-client) architecture in a world where east/west (server-to-server) traffic is becoming increasingly critical. Can UCS hold on in the face of a fundamental shift like that? I don’t know.
- Need to scramble some data on a block device? Check out this command. (I love the commandlinefu.com site. It reminds me that I still have so much yet to learn.)
Cloud Computing/Cloud Management
- Want to play around with OpenDaylight and OpenStack? Brent Salisbury has a write-up on how to OpenStack Icehouse (via DevStack) together with OpenDaylight.
- Puppet Labs has released a module that allows users to programmatically (via Puppet) provision and configure Google Compute Platform (GCP) instances. More details are available in the Puppet Labs blog post.
- I love how developers come up with these themes around certain projects. Case in point: “Heat” is the name of the project for orchestrating resources in OpenStack, HOT is the name for the format of Heat templates, and Flame is the name of a new project to automatically generate Heat templates.
- I can’t imagine that anyone has been immune to the onslaught of information on Docker, but here’s an article that might be helpful if you’re still looking for a quick and practical introduction.
- Many of you are probably familiar with Razor, the project that former co-workers Nick Weaver and Tom McSweeney created when they were at EMC. Tom has since moved on to CSC (via the vCHS team at VMware) and has launched a “next-generation” version of Razor called Hanlon. Read more about Hanlon and why this is a new/separate project in Tom’s blog post here.
- Looking for a bit of clarity around CoreOS and Project Atomic? I found this post by Major Hayden to be extremely helpful and informative. Both of these projects are on my radar, though I’ll probably focus on CoreOS first as the (currently) more mature solution.
- Linux Journal has a nice multi-page write-up on Docker containers that might be useful if you are still looking to understand Docker’s basic building blocks.
- I really enjoyed Donnie Berkholz’ piece on microservices and the migrating Unix philosophy. It was a great view into how composability can (and does) shift over time. Good stuff, I highly recommend reading it.
- cURL is an incredibly useful utility, especially in today’s age of HTTP-based REST API. Here’s a list of 9 uses for cURL that are worth knowing. This article on testing REST APIs with cURL is handy, too.
- And for something entirely different…I know that folks love to beat up AppleScript, but it’s cross-application tasks like this that make it useful.
- Someone recently brought the open source Open vStorage project to my attention. Open vStorage compares itself to VMware VSAN, but supporting multiple storage backends and supporting multiple hypervisors. Like a lot of other solutions, it’s implemented as a VM that presents NFS back to the hypervisors. If anyone out there has used it, I’d love to hear your feedback.
- Erik Smith at EMC has published a series of articles on “virtual storage networks.” There’s some interesting content there—I haven’t finished reading all of the posts yet, as I want to be sure to take the time to digest them properly. If you’re interested, I suggest starting out with his introductory post (which, strangely enough, wasn’t the first post in the series), then moving on to part 1, part 2, and part 3.
- Did you happen to see this write-up on migrating a VMware Fusion VM to VMware’s vCloud Hybrid Service? For now—I believe there are game-changing technologies out there that will alter this landscape—one of the very tangible benefits of vCHS is its strong interoperability with your existing vSphere (and Fusion!) workloads.
- Need a listing of the IP addresses in use by the VMs on a given Hyper-V host? Ben Armstrong shares a bit of PowerShell code that produces just such a listing. As Ben points out, this can be pretty handy when you’re trying to track down a particular VM.
- vCenter Log Insight 2.0 was recently announced; Vladan Seget has a decent write-up. I’m thinking of putting this into my home lab soon for gathering event information from VMware NSX, OpenStack, and the underlying hypervisors. I just need more than 24 hours in a day…
- William Lam has an article on lldpnetmap, a little-known utility for mapping ESXi interfaces to physical switches. As the name implies, this relies on LLDP, so switches that don’t support LLDP or that don’t have LLDP enabled won’t work correctly. Still, a useful utility to have in your toolbox.
- Technology previews of the next versions of Fusion (Fusion 7) and Workstation (Workstation 11) are available; see Eric Sloof’s articles (here and here for Fusion and Workstation, respectively) for more details.
- vSphere 4 (and associated pieces) are no longer under general support. Sad face, but time stops for no man (or product).
- Having some problems with VMware Fusion’s networking? Cody Bunch channels his inner Chuck Norris to kick VMware Fusion networking in the teeth.
- Want to preview OS X Yosemite? Check out William Lam’s guide to using Fusion or vSphere to preview the new OS X beta release.
I’d better wrap this up now, or it’s going to turn into one of Chad’s posts. (Just kidding, Chad!) Thanks for taking the time to read this far!
Tags: Automation, Fusion, Hardware, HyperV, Linux, Microsoft, Networking, Neutron, NSX, OpenStack, Puppet, SDN, Security, Storage, UCS, VMware
Welcome to Technology Short Take #41, the latest in my series of random thoughts, articles, and links from around the Internet. Here’s hoping you find something useful!
- Network Functions Virtualization (NFV) is a networking topic that is starting to get more and more attention (some may equate “attention” with “hype”; I’ll allow you to draw your own conclusion there). In any case, I liked how this article really hit upon what I personally feel is something many people are overlooking in NFV. Many vendors are simply rushing to provide virtualized versions of their solution without addressing the orchestration and automation side of the house. I’m looking forward to part 2 on this topic, in which the author plans to share more technical details.
- Rob Sherwood, CTO of Big Switch, recently published a reasonably in-depth look at “modern OpenFlow” implementations and how they can leverage multiple tables in hardware. Some good information in here, especially on OpenFlow basics (good for those of you who aren’t familiar with OpenFlow).
- Connecting Docker containers to Open vSwitch is one thing, but what about using Docker containers to run Open vSwitch in userspace? Read this.
- Ivan knocks centralized SDN control planes in this post. It sounds like Ivan favors scale-out architectures, not scale-up architectures (which are typically what is seen in centralized control plane deployments).
- Looking for more VMware NSX content? Anthony Burke has started a new series focusing on VMware NSX in pure vSphere environments. As far as I can tell, Anthony is up to 4 posts in the series so far. Check them out here: part 1, part 2, part 3, and part 4. Enjoy!
- Good friend Simon Seagrave is back to the online world again with this heads-up on a potential NIC issue with an HP Proliant firmware update. The post also contains a link to a fix for the issue. Glad to see you back again, Simon!
- Tom Howarth asks, “Is the x86 blade server dead?” (OK, so he didn’t use those words specifically. I’m paraphrasing for dramatic effect.) The basic premise of Tom’s position is that new technologies like server-side caching and VSAN/Ceph/Sanbolic (turning direct-attached storage into shared storage) will dramatically change the landscape of the data center. I would generally agree, although I’m not sure that I agree with Tom’s statement that “complexity is reduced” with these technologies. I think we’re just shifting the complexity to a different place, although it’s a place where I think we can better manage the complexity (and perhaps mask it). What do you think?
Cloud Computing/Cloud Management
- Juan Manuel Rey has launched a series of blog posts on deploying OpenStack with KVM and VMware NSX. He has three parts published so far; all good stuff. See part 1, part 2, and part 3.
- Kyle Mestery brought to my attention (via Twitter) this list of the “best newly-available OpenStack guides and how-to’s”. It was good to see a couple of Cody Bunch’s articles on the list; Cody’s been producing some really useful OpenStack content recently.
- I haven’t had the opportunity to use SaltStack yet, but I’m hearing good things about it. It’s always helpful (to me, at least) to be able to look at products in the context of solving a real-world problem, which is why seeing this post with details on using SaltStack to automate OpenStack deployment was helpful.
- Here’s a heads-up on a potential issue with the vCAC 22.214.171.124 upgrade—the upgrade apparently changes some configuration files. The linked blog post provides more details on which files get changed. If you’re looking at doing this upgrade, read this to make sure you aren’t adversely affected.
- Here’s a post with some additional information on OpenStack live migration that you might find useful.
- RHEL7, Docker, and Puppet together? Here’s a post on just such a use case (oh, I forgot to mention OpenStack’s involved, too).
- Have you ever walked through a spider web because you didn’t see it ahead of time? (Not very fun.) Sometimes I feel that way with certain technologies or projects—like there are connections there with other technologies, projects, trends, etc., that aren’t quite “visible” just yet. That’s where I am right now with the recent hype around containers and how they are going to replace VMs. I’m not so sure I agree with that just yet…but I have more noodling to do on the topic.
- “Server SAN” seems to be the name that is emerging to describe various technologies and architectures that create pools of storage from direct-attached storage (DAS). This would include products like VMware VSAN as well as projects like Ceph and others. Stu Miniman has a nice write-up on Server SAN over at Wikibon; if you’re not familiar with some of the architectures involved, that might be a good place to start. Also at Wikibon, David Floyer has a write-up on the rise of Server SAN that goes into a bit more detail on business and technology drivers, friction to adoption, and some recommendations.
- Red Hat recently announced they were acquiring Inktank, the company behind the open source scale-out Ceph project. Jon Benedict, aka “Captain KVM,” weighs in with his thoughts on the matter. Of course, there’s no shortage of thoughts on the acquisition—a quick web search will prove that—but I find it interesting that none of the “big names” in storage social media had anything to say (not that I could find, anyway). Howard? Stephen? Chris? Martin? Bueller?
- Doug Youd pulled together a nice summary of some of the issues and facts around routed vMotion (vMotion across layer 3 boundaries, such as across a Clos fabric/leaf-spine topology). It’s definitely worth a read (and not just because I get mentioned in the article, either—although that doesn’t hurt).
- I’ve talked before—although it’s been a while—about Hyper-V’s choice to rely on host-level NIC teaming in order to provide network link redundancy to virtual machines. Ben Armstrong talks about another option, guest-level NIC teaming, in this post. I’m not so sure that using guest-level teaming is any better than relying on host-level NIC teaming; what’s really needed is a more full-featured virtual networking layer.
- Want to run nested ESXi on vCHS? Well, it’s not supported…but William Lam shows you how anyway. Gotta love it!
- Brian Graf shows you how to remove IP pools using PowerCLI.
Well, that’s it for this time around. As always, I welcome all courteous comments, so feel free to share your thoughts, ideas, rants, links, or feedback in the comments below.
Tags: Hardware, HP, Networking, NSX, OpenFlow, OpenStack, OVS, Puppet, Security, SSL, Storage, VMotion, VMware, vSphere
Cody Bunch recently posted a quick round-up of what he carries when traveling, and just for fun I thought I’d do the same. Like Cody, I don’t know that I would consider myself a road warrior, but I have traveled a pretty fair amount. Here’s what I’m currently carrying when I hit the road:
- Light laptop and tablet: After years of carrying around a 15″ MacBook Pro, then going down to a 13″ MacBook Pro, I have to say I’m pretty happy with the 13" MacBook Air that I’m carrying now. Weight really does make a difference. I’m still toting the full-size iPad, but will probably switch to an iPad mini later in the year to save a bit more weight.
- Bag: I settled on the Timbuktu Commute messenger bag (see my write-up) and I’m quite pleased with it. A good bag makes a big difference when you’re mobile.
- Backup battery: I’m carrying the NewTrent PowerPak 10.0 (NT100H). It may not be the best product out there, but it’s worked pretty well for me. It’s not too heavy and not too big, and will charge both phones and tablets.
- Noise-canceling earphones: The Bose QC20 earphones (in-ear) are awesome. Naturally they let in a bit more noise than the bigger on-ear QC15 headphones, but the added noise is worth the tremendous decrease in size and weight.
On the software side, I’ll definitely echo Cody’s recommendation of Little Snitch; it’s a excellent product that I’ve used for years. You might also consider enabling the built-in firewall (see this write-up for enabling pf on OS X Mountain Lion; haven’t tried on Mavericks yet) for an added layer of network protection.
What about you, other road warriors out there? What are you carrying these days?
Update: Thanks to Ivan Pepelnjak, who pointed out that I had inadvertently swapped out the product names for the Bose earphones and headphones. That’s been corrected!
Tags: Hardware, Macintosh, Security
Welcome to Technology Short Take #40. The content is a bit light this time around; I thought I’d give you, my readers, a little break. Hopefully there’s still some useful and interesting stuff here. Enjoy!
- Bob McCouch has a nice write-up on options for VPNs to AWS. If you’re needing to build out such a solution, you might want to read his post for some additional perspectives.
- Matthew Brender touches on a networking issue present in VMware ESXi with regard to VMkernel multi-homing. This is something others have touched on before (including myself, back in 2008—not 2006 as I tweeted one day), but Matt’s write-up is concise and to the point. You’ll definitely want to keep this consideration in mind for your designs. Another thing to consider: vSphere 5.5 introduces the idea of multiple TCP/IP stacks, each with its own routing table. As the ability to use multiple TCP/IP stacks extends throughout vSphere, it’s entirely possible this limitation will go away entirely.
- YAOFC (Yet Another OpenFlow Controller), interesting only because it focuses on issues of scale (tens of thousands of switches with hundreds of thousands of endpoints). See here for details.
- Intel recently announced a refresh of the E5 CPU line; Kevin Houston has more details here.
- This one slipped past me in the last Technology Short Take, so I wanted to be sure to include it here. Mike Foley—whom I’m sure many of you know—recently published an ESXi security whitepaper. His blog post provides more details, as well as a link to download the whitepaper.
- The OpenSSL “Heartbleed” vulnerability has captured a great deal of attention (justifiably so). Here’s a quick article on how to assess if your Linux-based server is affected.
Cloud Computing/Cloud Management
- I recently built a Windows Server 2008 R2 image for use in my OpenStack home lab. This isn’t as straightforward as building a Linux image (no surprises there), but I did find a few good articles that helped along the way. If you find yourself needing to build a Windows image for OpenStack, check out creating a Windows image on OpenStack (via Gridcentric) and building a Windows image for OpenStack (via Brent Salisbury). You might also check out Cloudbase.it, which offers a version of cloud-init for Windows as well as some prebuilt evaluation images. (Note: I was unable to get the prebuilt images to download, but YMMV.)
- Speaking of building OpenStack images, here’s a “how to” guide on building a Debian 7 cloud image for OpenStack.
- Sean Roberts recently launched a series of blog posts about various OpenStack projects that he feels are important. The first project he highlights is Congress, a policy management project that has recently gotten a fair bit of attention (see a reference to Congress at the end of this recent article on the mixed messages from Cisco on OpFlex). In my opinion, Congress is a big deal, and I’m really looking forward to seeing how it evolves.
- I have a related item below under Virtualization, but I wanted to point this out here: work is being done on a VIF driver to connect Docker containers to Open vSwitch (and thus to OpenStack Neutron). Very cool. See here for details.
- I love that Cody Bunch thinks a lot like I do, like this quote from a recent post sharing some links on OpenStack Heat: “That generally means I’ve got way too many browser tabs open at the moment and need to shut some down. Thus, here comes a huge list of OpenStack links and resources.” Classic! Anyway, check out the list of Heat resources, you’re bound to find something useful there.
- A short while back I had a Twitter conversation about spinning up a Minecraft server for my kids in my OpenStack home lab. That led to a few other discussions, one of which was how cool it would be if you could use Heat autoscaling to scale Minecraft. Then someone sends me this.
- Per the Microsoft Windows Server Team’s blog post, the Windows Server 2012 R2 Udpate is now generally available (there’s also a corresponding update for Windows 8.1).
- Did you see that EMC released a virtual edition of VPLEX? It’s being called the “data plane” for software-defined storage. VPLEX is an interesting product, no doubt, and the introduction of a virtual edition is intriguing (but not entirely unexpected). I did find it unusual that the release of the virtual edition signalled the addition of a new feature called “MetroPoint”, which allows two sites to replicate back to a single site. See Chad Sakac’s blog post for more details.
- This discussion on MPIO and in-guest iSCSI is a great reminder that designing solutions in a virtualized data center (or, dare I say it—a software-defined data center?) isn’t the same as designing solutions in a non-virtualized environment.
- Ben Armstrong talks briefly about Hyper-V protected networks, which is a way to protect a VM against network outage by migrating the VM to a different host if a link failure occurs. This is kind of handy, but requires Windows Server clustering in order to function (since live migration in Hyper-V requires Windows Server clustering). A question for readers: is Windows Server clustering still much the same as it was in years past? It was a great solution in years past, but now it seems outdated.
- At the same time, though, Microsoft is making some useful networking features easily accessible in Hyper-V. Two more of Ben’s articles show off the DHCP Guard and Router Guard features available in Hyper-V on Windows Server 2012.
- There have been a pretty fair number of posts talking about nested ESXi (ESXi running as a VM on another hypervisor), either on top of ESXi or on top of VMware Fusion/VMware Workstation. What I hadn’t seen—until now—was how to get that working with OpenStack. Here’s how Mathias Ewald made it work.
- And while we’re talking nested hypervisors, be sure to check out William Lam’s post on running a nested Xen hypervisor with VMware Tools on ESXi.
- Check out this potential way to connect Docker containers with Open vSwitch (which then in turn opens up all kinds of other possibilities).
- Jason Boche regales us with a tale of a vCenter 5.5 Update 1 upgrade that results in missing storage providers. Along the way, he also shares some useful information about Profile-Driven Storage in general.
- Eric Gray shares information on how to prepare an ESXi ISO for PXE booting.
- PowerCLI 5.5 R2 has some nice new features. Skip over to Alan Renouf’s blog to read up on what is included in this latest release.
I should close things out now, but I do have one final link to share. I really enjoyed Nick Marshall’s recent post about the power of a tweet. In the post, Nick shares how three tweets—one with Duncan Epping, one with Cody Bunch, and one with me—have dramatically altered his life and his career. It’s pretty cool, if you think about it.
Anyway, enough is enough. I hope that you found something useful here. I encourage readers to contribute to the discussion in the comments below. All courteous comments are welcome.
Tags: Hardware, HyperV, iSCSI, Networking, OpenStack, Security, Storage, Virtualization, VMware, VPLEX, vSphere, Windows
Welcome to Technology Short Take #39, in which I share a random assortment of links, articles, and thoughts from around the world of data center-related technologies. I hope you find something useful—or at least something interesting!
- Jason Edelman has been talking about the idea of a Common Programmable Abstraction Layer (CPAL). He introduces the idea, then goes on to explore—as he puts it—the power of a CPAL. I can’t help but wonder if this is the right level at which to put the abstraction layer. Is the abstraction layer better served by being integrated into a cloud management platform, like OpenStack? Naturally, the argument then would be, “Not everyone will use a cloud management platform,” which is a valid argument. For those customers who won’t use a cloud management platform, I would then ask: will they benefit from a CPAL? I mean, if they aren’t willing to embrace the abstraction and automation that a cloud management platform brings, will abstraction and automation at the networking layer provide any significant benefit? I’d love to hear others’ thoughts on this.
- Ethan Banks also muses on the need for abstraction.
- Craig Matsumoto of SDN Central helps highlight a recent (and fairly significant) development in networking protocols—the submission of the Generic Network Virtualization Encapsulation (Geneve) proposal to the IETF. Jointly authored by VMware, Microsoft, Red Hat, and Intel, this new protocol proposal attempts to bring together the strengths of the various network virtualization encapsulation protocols out there today (VXLAN, STT, NVGRE). This is interesting enough that I might actually write up a separate blog post about it; stay tuned for that.
- Lee Doyle provides an analysis of the market for network virtualization, which includes some introductory information for those who might be unfamiliar with what network virtualization is. I might contend that Open vSwitch (OVS) alone isn’t an option for network virtualization, but that’s just splitting hairs. Overall, this is a quick but worthy read if you are trying to get started in this space.
- Don’t think this “software-defined networking” thing is going to take off? Read this, and then let me know what you think.
- Chris Margret has a nice dissection of how bash completion works, particularly in regards to the Cumulus Networks implementation.
- Via Kevin Houston, you can get more details on the Intel E7 v2 and new blade servers based on the new CPU. x86 marches on!
- Another interesting tidbit regarding hardware: it seems as if we are now seeing the emergence of another round of “hardware offloads.” The first round came about around 2006 when Intel and AMD first started releasing their hardware assists for virtualization (Intel VT and AMD-V, respectively). That technology was only “so-so” at first (VMware ESX continued to use binary translation [BT] because it was still faster than the hardware offloads), but it quickly matured and is now leveraged by every major hypervisor on the market. This next round of hardware offloads seems targeted at network virtualization and related technologies. Case in point: a relatively small company named Netronome (I’ve spoken about them previously, first back in 2009 and again a year later), recently announced a new set of network interface cards (NICs) expressly designed to provide hardware acceleration for software-defined networking (SDN), network functions virtualization (NFV), and network virtualization solutions. You can get more details from the Netronome press release. This technology is actually quite interesting; I’m currently talking with Netronome about testing it with VMware NSX and will provide more details as that evolves.
- Ben Rossi tackles the subject of security in a software-defined world, talking about how best to integrate security into SDN-driven architectures and solutions. It’s a high-level article and doesn’t get into a great level of detail, but does point out some of the key things to consider.
Cloud Computing/Cloud Management
- “Racker” James Denton has some nice articles on OpenStack Neutron that you might find useful. He starts out with discussing the building blocks of Neutron, then goes on to discuss building a simple flat network, using VLAN provider networks, and Neutron routers and the L3 agent. And if you need a breakdown of provider vs. tenant networks in Neutron, this post is also quite handy.
- Here’s a couple (first one, second one) of quick walk-throughs on installing OpenStack. They don’t provide any in-depth explanations of what’s going on, why you’re doing what you’re doing, or how it relates to the rest of the steps, but you might find something useful nevertheless.
- Thinking of building your own OpenStack cloud in a home lab? Kevin Jackson—who along with Cody Bunch co-authored the OpenStack Cloud Computing Cookbook, 2nd Edition—has three articles up on his home OpenStack setup. (At least, I’ve only found three articles so far.) Part 1 is here, part 2 is here, and part 3 is here. Enjoy!
- This post attempts to describe some of the core (mostly non-technical) differences between OpenStack and OpenNebula. It is published on the OpenNebula.org site, so keep that in mind as it is (naturally) biased toward OpenNebula. It would be quite interesting to me to see a more technically-focused discussion of the two approaches (and, for that matter, let’s include CloudStack as well). Perhaps this already exists—does anyone know?
- CloudScaling recently added a Google Compute Engine (GCE) API compatibility module to StackForge, to allow users to leverage the GCE API with OpenStack. See more details here.
- Want to run Hyper-V in your OpenStack environment? Check this out. Also from the same folks is a version of cloud-init for Windows instances in cloud environments. I’m testing this in my OpenStack home lab now, and hope to have more information soon.
- Brendan Gregg of Joyent has an interesting write-up comparing virtualization performance between Zones (apparently referring to Solaris Zones, a form of OS virtualization/containerization), Xen, and KVM. I might disagree that KVM is a Type 2 hardware virtualization technology, pointing out that Xen also requires a Linux-based dom0 in order to function. (The distinction between a Type 1 that requires a general purpose OS in a dom0/parent partition and a Type 2 that runs on top of a general purpose OS is becoming increasingly blurred, IMHO.) What I did find interesting was that they (Joyent) run a ported version of KVM inside Zones for additional resource controls and security. Based on the results of his testing—performed using DTrace—it would seem that the “double-hulled virtualization” doesn’t really impact performance.
- Pete Koehler—via Jason Langer’s blog—has a nice post on converting in-guest iSCSI volumes to native VMDKs. If you’re in a similar situation, check out the post for more details.
- This is interesting. Useful, I’m not so sure about, but definitely interesting.
- If you are one of the few people living under a rock who doesn’t know about PowerCLI, Alan Renouf is here to help.
It’s time to wrap up; this post has already run longer than usual. There was just so much information that I want to share with you! I’ll be back soon-ish with another post, but until then feel free to join (or start) the conversation by adding your thoughts, ideas, links, or responses in the comments below.
Tags: Hardware, Intel, iSCSI, Networking, Neutron, NSX, OpenStack, OVS, Security, Storage, Virtualization, VSAN, Windows
Welcome to Technology Short Take #36. In this episode, I’ll share a variety of links from around the web, along with some random thoughts and ideas along the way. I try to keep things related to the key technology areas you’ll see in today’s data centers, though I do stray from time to time. In any case, enough with the introduction—bring on the content! I hope you find something useful.
- This post is a bit older, but still useful in the event if you’re interested in learning more about OpenFlow and OpenFlow controllers. Nick Buraglio has put together a basic reference OpenFlow controller VM—this is a KVM guest with CentOS 6.3 with the Floodlight open source controller.
- Paul Fries takes on defining SDN, breaking it down into two “flavors”: host dominant and network dominant. This is a reasonable way of grouping the various approaches to SDN (using SDN in the very loose industry sense, not the original control plane-data plane separation sense). I’d like to add to Paul’s analysis that it’s important to understand that, in reality, host dominant and network dominant systems can coexist. It’s not at all unreasonable to think that you might have a fabric controller that is responsible for managing/optimizing traffic flows across the physical transport network/fabric, and an overlay controller—like VMware NSX—that integrates tightly with the hypervisor(s) and workloads running on those hypervisors to create and manage logical connectivity and logical network services.
- This is an older post from April 2013, but still useful, I think. In his article titled “OpenFlow Test Deployment Options“, Brent Salisbury—a rock star new breed network engineer emerging in the new world of SDN—discusses some practical deployment strategies for deploying OpenFlow into an existing network topology. One key statement that I really liked from this article was this one: “SDN does not represent the end of networking as we know it. More than ever, talented operators, engineers and architects will be required to shape the future of networking.” New technologies don’t make talented folks who embrace change obsolete; if anything, these new technologies make them more valuable.
- Great post by Ivan (is there a post by Ivan that isn’t great?) on flow table explosion with OpenFlow. He does a great job of explaining how OpenFlow works and why OpenFlow 1.3 is needed in order to see broader adoption of OpenFlow.
- Intel announced the E5 2600 v2 series of CPUs back at Intel Developer Forum (IDF) 2013 (you can follow my IDF 2013 coverage by looking at posts with the IDF2013 tag). Kevin Houston followed up on that announcement with a useful post on vSphere compatibility with the E5 2600 v2. You can also get more details on the E5 2600 v2 itself in this related post by Kevin as well. (Although I’m just now catching Kevin’s posts, they were published almost immediately after the Intel announcements—thanks for the promptness, Kevin!)
Nothing this time around, but I’ll keep my eyes posted for content to share with you in future posts.
Cloud Computing/Cloud Management
- I found this refresher on some of the most useful apt-get/apt-cache commands to be helpful. I don’t use some of them on a regular basis, and so it’s hard to remember the specific command and/or syntax when you do need one of these commands.
- I wouldn’t have initially considered comparing Docker and Chef, but considering that I’m not an expert in either technology it could just be my limited understanding. However, this post on why Docker and why not Chef does a good job of looking at ways that Docker could potentially replace certain uses for Chef. Personally, I tend to lean toward the author’s final conclusions that it is entirely possible that we’ll see Docker and Chef being used together. However, as I stated, I’m not an expert in either technology, so my view may be incorrect. (I reserve the right to revise my view in the future.)
- Using Dell EqualLogic with VMFS? Better read this heads-up from Cormac Hogan and take the recommended action right away.
- Erwin van Londen proposes some ideas for enhancing FC error detection and notification with the idea of making hosts more aware of path errors and able to “route” around them. It’s interesting stuff; as Erwin points out, though, even if the T11 accepted the proposal it would be a while before this capability showed up in actual products.
- Libguestfs is an interesting project, and in the 1.24 release they added a tool called virt-builder that helps quickly and easily deploy VM images.
- Andre Leibovici is well-known for his insightful and informative coverage of Horizon View and related products/technologies, and rightfully so. As proof of that, I recently came across two articles by Andre, one on why CBRC is so important for Horizon View and VSAN, and a second on how VSAN helps Horizon View. Both of these are definitely worth reading if you want a bit more detail on how one of VMware’s newest technologies, VSAN, is going to impact the end-user computing (EUC) space.
- Speaking of VSAN, William Lam has a very useful article on the additional steps that are required to completely disable VSAN on an ESXi host. I indicate that this is useful because I anticipate many folks will want to try out VSAN in their lab first. Since you will likely then want to take it out of the lab and move it into production after the appropriate amount of testing and validation for your environment, this post is quite helpful.
- It’s kind of funny: I was doing a bit of reading on ZeroVM, a new open source lightweight hypervisor, trying to understand where it fits in the overall virtualization space. The very next day, I see the announcement that ZeroVM is being acquired by Rackspace. Anyone want to take guesses on when we’ll see ZeroVM support in OpenStack?
- Nice write-up by Gabrie Van Zanten on a potential connection issue with the VCSA in vSphere 5.5.
- See this post by Ben Armstrong on faster live migration in Hyper-V on Windows Server 2012 R2 (which is now generally available).
That’s it for this time around, but feel free to continue to conversation in the comments below. If you have any additional information to share regarding any of the topics I’ve mentioned, please take the time to add that information in the comments. Courteous comments are always welcome!
Tags: Automation, CLI, Hardware, HyperV, Linux, Networking, OpenFlow, OpenStack, Puppet, Security, Storage, Virtualization, VMware
Welcome to Technology Short Take #35, another in my irregular series of posts that collect various articles, links and thoughts regarding data center technologies. I hope that something in here is useful to you.
- Art Fewell takes a deeper look at the increasingly important role of the virtual switch.
- A discussion of “statefulness” brought me again to Ivan’s post on the spectrum of firewall statefulness. It’s so easy sometimes just to revert to “it’s stateful” or “it’s not stateful,” but the reality is that it’s not quite so black-and-white.
- Speaking of state, I like this piece by Ivan as well.
- I tend not to link to TechTarget posts any more than I have to, because invariably the articles end up going behind a login requirement just to read them. Even so, this Q&A session with Martin Casado on managing physical and virtual worlds in parallel might be worth going through the hassle.
- This looks interesting.
- VMware introduced VMware NSX recently at VMworld 2013. Cisco shared some thoughts on what they termed a “software-only” approach; naturally, they have a different vision for data center networking (and that’s OK). I was a bit surprised by some of the responses to Cisco’s piece (see here and here). In the end, though, I like Greg Ferro’s statement: “It is perfectly reasonable that both companies will ‘win’.” There’s room for a myriad of views on how to solve today’s networking challenges, and each approach has its advantages and disadvantages.
Nothing this time around, but I’ll watch for items to include in future editions. Feel free to send me links you think would be useful to include in the future!
- I found this write-up on using OVS port mirroring with Security Onion for intrusion detection and network security monitoring.
Cloud Computing/Cloud Management
- Prasenjit Sarkar, who works in VMware R&D, and runs the Stretch Cloud site, has a write-up on using Data Center Extension (DCE) to VMware vCloud Hybrid Service (vCHS). It’s a pretty detailed write-up, with step-by-step instructions and lots of screenshots. His follow-up article on disaster recovery of DCE VM with vCHS is also pretty good. If you’re considering how you might be able to use vCHS for your organization, these articles might really be worth your time.
- Chris Colotti has also been tackling some vCHS stuff. Relative to using DCE, Chris’ post on what’s required for vSphere Stretch Deploy to work with vCHS is quite useful. Also be sure to check out his two-part series on using Stretch Deploy with vCHS (part 1 and part 2). Finally, Chris’ post on migrating VMs to vCHS (the so-called “V2C” migration) is also a good article.
- I liked this write-up on the combination of Puppet, Hiera, OpenStack, and Vagrant.
- Kenneth Hui, formerly of VCE and now with Rackspace, does a great job of explaining how VMware vSphere fits into the OpenStack Nova architecture in this blog post. He also has a series of blog posts running on his own site on OpenStack compute for vSphere admins (part 1, part 2, part 3, part 4, and part 5). Very good stuff!
- In past presentations I’ve referenced the terms “snowflake servers” and “phoenix servers,” which I borrowed from Martin Fowler. (I don’t know if Martin coined the terms or not, but you can get more information here and here.) Recently among some of Martin’s material I saw reference to yet another term: the immutable server. It’s an interesting construct: rather than managing the configuration of servers, you simply spin up new instances when you need a new configuration; existing configurations are never changed. More information on the use of the immutable server construct is also available here. I’d be interested to hear readers’ thoughts on this idea.
- Chris Evans takes a took at ScaleIO, recently acquired by EMC, and speculates on where ScaleIO fits into the EMC family of products relative to the evolution of storage in the data center.
- While I was at VMworld 2013, I had the opportunity to talk with SanDisk’s FlashSoft division about their flash caching product. It was quite an interesting discussion, so stay tuned for that update (it’s almost written; expect it in the next couple of days).
- The rise of new converged (or, as some vendors like to call it, “hyperconverged”) architectures means that we have to consider the impact of these new architectures when designing vSphere environments that will leverage them. I found a few articles by fellow VCDX Josh Odgers that discuss the impact of Nutanix’s converged architecture on vSphere designs. If you’re considering the use of Nutanix, have a look at some of these articles (see here, here, and here).
- Jonathan Medd shows how to clone a VM from a snapshot using PowerCLI. Also be sure to check out this post on the vSphere CloneVM API, which Jonathan references in his own article.
- Andre Leibovici shares an unofficial way to disable the use of the SESparse disk format and revert to VMFS Sparse.
- Forgot the root password to your ESXi 5.x host? Here’s a procedure for resetting the root password for ESXi 5.x that involves booting on a Linux CD. As is pointed out in the comments, it might actually be easier to rebuild the host.
- vSphere 5.5 was all the rage at VMworld 2013, and there was a lot of coverage. One thing that I didn’t see much discussion around was what’s going on with the free version of ESXi. Vladan Seget gives a nice update on how free ESXi is changing with version 5.5.
- I am loving the micro-infrastructure series by my VMware vSphere Design co-author, Forbes Guthrie. See it here, here, and here.
It’s time to wrap up now; I’ve already included more links than I normally include (although it doesn’t seem like it). In any case, I hope that something I’ve shared here is helpful, and feel free to share your own thoughts, ideas, and feedback in the comments below. Have a great day!
Tags: CLI, Networking, OpenFlow, OpenStack, Puppet, Security, Storage, Virtualization, VMware, vSphere
Welcome to Technology Short Take #33, the latest in my irregularly-published series of articles discussing various data center technology-related links, articles, rants, thoughts, and questions. I hope that you find something useful here. Enjoy!
- Tom Nolle asks the question, “Is virtualization reality even more elusive than virtual reality?” It’s a good read; the key thing that I took away from it was that SDN, NFV, and related efforts are great, but what we really need is something that can pull all these together in a way that customers (and providers) reap the benefits.
- What happens when multiple VXLAN logical networks are mapped to the same multicast group? Venky explains it in this post. Venky also has a great write-up on how the VTEP (VXLAN Tunnel End Point) learns and creates the forwarding table.
- This post by Ranga Maddipudi shows you how to use App Firewall in conjunction with VXLAN logical networks.
- Jason Edelman is on a roll with a couple of great blog posts. First up, Jason goes off on a rant about network virtualization, briefly hitting topics like the relationship between overlays and hardware, the role of hardware in network virtualization, the changing roles of data center professionals, and whether overlays are the next logical step in the evolution of the network. I particularly enjoyed the snippet from the post by Bill Koss. Next, Jason dives a bit deeper on the relationship between network overlays and hardware, and shares his thoughts on where it does—and doesn’t—make sense to have hardware terminating overlay tunnels.
- Another post by Tom Nolle explores the relationship—complicated at times—between SDN, NFV, and the cloud. Given that we define the cloud (sorry to steal your phrase, Joe) as elastic, pooled resources with self-service functionality and ubiquitous access, I can see where Tom states that to discuss SDN or NFV without discussing cloud is silly. On the flip side, though, I have to believe that it’s possible for organizations to make a gradual shift in their computing architectures and processes, so one almost has to discuss these various components individually, because to tie them all together makes it almost impossible. Thoughts?
- If you haven’t already introduced yourself to VXLAN (one of several draft protocols used as an overlay protocol), Cisco Inferno has a reasonable write-up.
- I know Steve Jin, and he’s a really smart guy. I must disagree with some of his statements regarding what software-defined networking is and is not and where it fits, written back in April. I talked before about the difference between network virtualization and SDN, so no need to mention that again. Also, the two key flaws that Steve identifies—single point of failure and scalability—aren’t flaws with SDN/network virtualization, but rather flaws in an implementation of said technologies, IMHO.
- Correction from the last Technology Short Take—I incorrectly stated that the HP Moonshot offerings were ARM-based, and therefore wouldn’t support vSphere. I was wrong. The servers (right now, at least) are running Intel Atom S1260 CPUs, which are x86-based and do offer features like Intel VT-x. Thanks to all who pointed this out, and my apologies for the error!
- I missed this on the #vBrownBag series: designing HP Virtual Connect for vSphere 5.x.
Cloud Computing/Cloud Management
- Hyper-V as hypervisor with OpenStack Compute? Sure, see here.
- Cody Bunch, who has been focusing quite a bit on OpenStack recently, has a nice write-up on using Razor and Chef to automate an OpenStack build. Part 1 is here; part 2 is here. Good stuff—keep it up, Cody!
- I’ve mentioned in some of my OpenStack presentations (see SpeakerDeck or Slideshare) that a great place to start if you’re just getting started is DevStack. Here, Brent Salisbury has a nice write-up on using DevStack to install OpenStack Grizzly.
- Boxen, a tool created by GitHub to manage their OS X Mountain Lion laptops for developers, looks interesting. Might be a useful tool for other environments, too.
- If you use TextMate2 (I switched to BBEdit a little while ago after being a long-time TextMate user), you might enjoy this quick post by Colin McNamara on Puppet syntax highlighting using TextMate2.
- Anyone have more information on Jeda Networks? They’ve been mentioned a couple of times on GigaOm (here and here), but I haven’t seen anything concrete yet. Hey, Stephen Foskett, if you’re reading: get Jeda Networks to the next Tech Field Day.
- Tim Patterson shares some code from Luc Dekens that helps check VMFS version and block sizes using PowerCLI. This could come in quite handy in making sure you know how your datastores are configured, especially if you are in the midst of a migration or have inherited an environment from someone else.
- Interested in using SAML and Horizon Workspace with vCloud Director? Tom Fojta shows you how.
- If you aren’t using vSphere Host Profiles, this write-up on the VMware SMB blog might convince you why you should and show you how to get started.
- Michael Webster tackles the question: is now the best time to upgrade to vSphere 5.1? Read the full post to see what Michael has to say about it.
- Duncan points out an easy error to make when working with vSphere HA heartbeat datastores in this post. Key takeaway: sometimes the fix is a lot simpler than we might think at first. (I know I’m guilty of making things more complicated than they need to be at times. Aren’t we all?)
- Jon Benedict (aka “Captain KVM”) shares a script he wrote to help provide high availability for RHEV-M.
- Chris Wahl has a nice write-up on using log shipping to protect your vCenter database. It’s a bit over a year old (surprised I missed it until now), and—as Chris points out—log shipping doesn’t protect the database (primary and secondary copies) against corruption. However, it’s better than nothing (which I suspect it what far too many people are using).
- If you aspire to be a writer—whether that be a blogger, author, journalist, or other—you might find this article on using the DASH method for writing to be helpful. The six tips at the end of the article are especially helpful, I think.
Time to wrap this up for now; the rest will have to wait until the next Technology Short Take. Until then, feel free to share your thoughts, questions, or rants in the comments below. Courteous comments are always welcome!
Tags: Automation, Hardware, HP, HyperV, Linux, Macintosh, Networking, OpenStack, Puppet, SDN, vCloud, Virtualization, vSphere, VXLAN, Writing