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A Couple GeekTool Scripts

Monday, January 11, 2010 in Macintosh, UNIX by slowe | 1 comment

I’ve been experimenting with GeekTool, a nifty Mac OS X Preference Pane that allows you to display information on your desktop. This information can be static text, images, or the output of a script. The last option is the most useful one, in my opinion, and that’s where I’ve been putting GeekTool to use for me. This isn’t going to be some long post on how to use GeekTool or why you should install it; rather, I just wanted to share a couple of short scripts that I wrote that you might find useful.

I use Mac OS X’s network location support extensively. I have separate locations for home (where I have a proxy server) and when I’m out and about (where there generally is no proxy server). So it’s important for me to be able to tell, quickly, which location is active. If the wrong location is active, then network connectivity is impaired.

To help, I use this command with GeekTool to display the network location on my desktop:

echo "Location: `networksetup -getcurrentlocation 2>&1 | tail -n 1`"

Note that if you are running as an administrative user on your Mac (which I don’t in order to reduce potential security risks), then the networksetup command I use above will probably behave differently for you. Since I’m not running as an administrative user, networksetup would throw an error at the command line. Thus why I had to redirect STDERR to STDOUT and filter it using tail. Now, a quick F11 to show the desktop and I can immediately see which network location is active.

I also recently added a script to show me what proxy servers are currently active. This is in anticipation of starting my new job at EMC. I don’t know if they have proxy servers on their network, but in the event they do I thought this next command might be handy:

echo "HTTP Proxy: `scutil --proxy | grep HTTP | sort | sed -n '3,3p' | awk '{print $3}'`"

This command displays the HTTP proxy host configured in your network settings. So, again, a quick F11 allows me to see which proxy hosts are configured and active on my Mac.

I actually wrapped several of these commands together into a shell script that you can download here if you’d like. I’m sure there is probably some bash black magic that could produce this output in a more efficient way; feel free to post suggestions for improvement if you have any!

Of course, I also have a few other scripts running with GeekTool—one that displays system information, one that produces IP addresses and Airport (wireless LAN) information, etc.—but these two are probably most useful to me so far.

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Virtualization Short Take #33

Thursday, January 7, 2010 in Virtualization by slowe | 3 comments

Welcome to Virtualization Short Take #33, the first installation of the Virtualization Short Take series for 2010! This installation will be a bit lean, but I hope that you find something useful among these nuggets of information.

  • This article by Kenneth Van Ditmarsch, backed up by this post by Chad Sakac, underscore the need for proper operational documentation for your virtualization environment. Organizations that have taken the time to prepare operational procedures and train their staff on using the documented procedures will, in my opinion, be far less likely to fall victim to this vSphere storage bug. I’m not saying you’ve got to go crazy on documentation, but take the time to document and validate the core procedures your team is using. I think you’ll find the results beneficial.
  • Speaking of vSphere bugs, Chad also describes a bug affecting vSphere 4 (including Update 1) involving NMP and Round Robin. If you change the I/O Operation Limit for Round Robin (using the esxcli command), you might find that the value gets changed to some random value upon reboot. The workaround is to not modify the I/O Operation Limit (the default value is 1000).
  • Scott Drummonds of VMware has been publishing a great series of articles on host swapping and memory overcommit. The series starts with a discussion on host swapping and the fact that VMware ESX does not track working sets within every VM (it would be too much overhead). He continues with this post on using SSDs to help alleviate potential host swapping performance concerns (also see this article that Scott references in his post). In the last two posts, Scott debunks some misconceptions about memory management and then goes to show why memory overcommit is important in optimizing memory utilization. Definitely some good stuff.
  • The VMware Communities blog post about using SSDs to improve performance when memory is overcommitted (found here) put me to thinking. In the tests documented in that post, local SSDs were used. What if EFDs were used instead? I’d be curious to know the results. This would support a boot from SAN approach that is more amenable to Cisco UCS model of stateless computing (although I’ve said before that I’m not entirely sold on stateless computing in a virtualized environment, since the hypervisor negates some of the benefits).
  • There are some areas where the Cisco UCS stateless computing model really shines; Steve Chambers describes one such use case in this post on multi-tenant DR with Cisco UCS.
  • Here’s a useful document on installing VMware ESXi on Cisco UCS using the UCS Manager KVM. Last time I tried the UCS Manager KVM on my Mac, it was barely usable and you couldn’t attach media; hopefully it’s improved since then.
  • Arnim van Lieshout has a great post on geographically dispersed VMware clusters. One thought that occurred to me as I was reading this post was that while Arnim’s post was written from the perspective of a production site and a DR site, the same challenges affect the use of external cloud providers and vCloud. As VMware and VMware’s partners start to address these challenges, not only does the idea of geographically dispersed clusters start to look more realistic and more flexible, but so too does the idea of leveraging additional capacity from a cloud provider via vCloud.
  • Interested in triggering an ESXi kernel panic on demand? Eric Sloof shows you how.
  • Finally, for users with the Nexus 1000V who want to update their ESX/ESXi hosts to Update 1 using the vihostupdate utility, Duncan’s post (and this associated VMware KB article) provides all the information necessary to make it work properly.

I did find a couple other useful posts that I haven’t had the time to properly read but which look interesting:

VMware Desktop Reference Architecture Workload Simulator (RAWC)
White Paper: VMware vSphere 4 Performance with Extreme I/O Workloads

That’s it for this time around. I welcome all courteous comments or thoughts on any of the links or posts I’ve mentioned here. Thanks for reading!

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VMware, Zimbra, and Why I’m Not an Analyst

Tuesday, January 5, 2010 in Collaboration, Messaging, Virtualization by slowe | 8 comments

The rumors are swirling that VMware is going to buy Zimbra, an open source e-mail platform currently owned by Yahoo. You’ve probably all read the various news articles about the rumors and the events leading up to the rumored acquisition, so I won’t bother you with them again.

Yesterday on Twitter, I mentioned that the Zimbra acquisition didn’t quite make sense to me. I wasn’t the only one; several others mentioned it, too. That sparked a great discussion with Chris Wolf of the Burton Group (really sharp guy, by the way). His comments caused me to look at the purported acquisition in a different light where it starts to make a bit more sense. The discussion reminded me why I’m not an analyst: sometimes I don’t take a broad enough view. (It’s something I’ll work on improving.)

Most people look at the Zimbra acquisition (assuming that the rumor is accurate and it really does happen) and immediately recognize the intent to compete against Microsoft Exchange. However, if you look at the Zimbra acquisition strictly from the perspective of competing against Microsoft Exchange in the market as it currently exists, you’ll quickly come to the same conclusion that I did: it doesn’t make sense. Get real: lots of companies have tried before and failed. I believe that If VMware were to use Zimbra to compete against Exchange in the traditional corporate messaging market, where Exchange mopped up very worthy competitors like Lotus Notes, VMware would end up a failure like so many others before them. As Chris Wolf pointed out on Twitter, the integration between Exchange and the Microsoft applications is just too great to take them head-on.

However, what if you consider that the market is shifting? There is a greater move toward private clouds running scalable, web-based applications. There is an inclination toward workloads that can run outside of an organization’s data center. There is a shift toward virtual desktops. There is desire and interest in embracing the idea of cloud computing—however you choose to define that—across organizations of many different shapes and sizes. In the light of these market factors, now the Zimbra acquisition starts to make more sense. Yes, VMware will compete against Microsoft with Zimbra, but not using today’s architectures and today’s paradigms. As Chris put it in a Twitter post yesterday (emphasis mine):

@TonyWilburn @scott_lowe - IMO vmware has to redefine the traditional app stack for long term survival; email has to be part of it

In the light of this line of thinking, the acquisition begins to make a bit more sense (again, assuming that it’s actually going to happen). Although VMware has different leadership, and it’s a different market, I do feel that VMware would not be successful taking on Microsoft Exchange without redefining how e-mail platforms—as a key part of the overall application stack—can be provisioned, deployed, and managed in conjunction with VMware’s broader private cloud/public cloud strategy.

So what do you think?

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Vote Early (But Don’t Vote Often)

Monday, January 4, 2010 in General, Networking, Storage, Virtualization by slowe | 1 comment

The time has come again for readers to vote for Eric Siebert’s top 20 bloggers list. I’ve been honored to be placed at #2 for quite some time now, behind Duncan Epping and ahead of Chad Sakac. In addition, some great new bloggers have arrived on the scene this past year, so the competition is going to be fierce. I hope to retain or improve my position, but I’m also realistic—there are some really great bloggers out there.

In addition, my blogging frequency was down this past year because of the two books I wrote this year, Mastering VMware vSphere 4 and VMware vSphere 4 Administration Instant Reference (with Jase McCarty and Matthew Johnson).

Still, the site has a sizable following. I’m averaging around 7,700 RSS subscribers, and the site is getting around 100,000 visits a month (depending upon which statistics mechanism you use, sometimes higher and sometimes lower). Anecdotally, I’ve had a few other bloggers tell me that their traffic spikes whenever I link to one of their posts. I guess I must be doing something right!

Luckily, I have gotten a few good posts out this year:

Creating a Bootable ESXi USB Stick on Mac OS X
vSphere Virtual Machine Upgrade Process
VMware vSphere vDS, VMkernel Ports, and Jumbo Frames
New User’s Guide to Configuring VMware ESX Networking via CLI
Introduction to Nehalem Memory (by guest author Aaron Delp)
Using VMware ESX Virtual Switch Tagging with HP Virtual Connect
Another Reason Not to Use PVSCSI or VMXNET3

And those are just the virtualization-related posts…I’ve also expanded into more SAN-related posts (a couple of Cisco MDS posts here and here), an introductory post on SR-IOV here, and some FCoE posts (here and here, for example).

So, if you could find it in your hearts to vote for me, I’d certainly appreciate it. Go vote now!

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Staying in Touch with Me

Monday, January 4, 2010 in General by slowe | 2 comments

With the job change, some of my contact information is also changing. Naturally, my ePlus.com e-mail address will go away, but also going away (effective immediately) are my three ePlus-related instant messaging accounts:

MSN Messenger (slowe@eplus.com)
Yahoo Messenger (eplusslowe)
AOL Instant Messenger (eplusslowe)

If you are using my ePlus e-mail address or any of these instant messaging accounts to stay in touch with me, you’ll need to update your contact information. I don’t have my official EMC e-mail address yet, but my personal e-mail address is available on the About page of this site. I also have Google Talk, AIM, and MSN Messenger accounts that use my personal e-mail address as the user ID; you can use these as a replacement for the ePlus-related instant messaging accounts. I won’t be creating a new Yahoo Messenger account.

If you have my Google Voice number, you can continue using that number to reach me via telephone or SMS. Otherwise, all my old phone numbers will go away. And no, I’m not going to post my Google Voice number out here for anyone to use. Those of you that need it should already have it.

My Twitter ID (scott_lowe) and my blog URL will remain unchanged. I will continue to actively use both to share useful technical information.

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So Long Status Quo

Monday, December 28, 2009 in General, Personal by slowe | 50 comments

Fans of Christian artist Nichole Nordeman will recognize the title of this post as a line coming from the chorus of her hit song “Brave” (from the album of the same name). The words go something like this:

So long status quo,
I think I just let go…

I think that these words are particularly applicable given the decision that I’ve just made. Talk about letting go of the status quo! You see, for the largest part of my professional career I’ve worked in the partner/reseller community. Working in the partner/reseller community has been great; you get to meet lots of different people, work in a variety of environments, and constantly chase the latest technologies. Still, the demands of the partner/reseller community almost force you, as a technical person, to be “a mile wide but only an inch deep,” meaning you know only a little bit about a lot of things. That can be difficult for some people, like me, who like to really know products. A lot of times, you just don’t get the time to do that. In a couple of weeks, though, all that changes.

In a couple of weeks, I’ll be joining EMC Corporation as a VMware-Cisco Solutions Principal. Yes, that’s right—I’m joining Chad’s team (sometimes referred to as “Chad’s Army”). I can’t tell you yet if I’m a warrior, a monk, a warrior-monk, or something else entirely; I imagine that will be just one of many things that I will discover in the coming months and years.

I can tell you that I’m very excited. As indicated by my job title, I’ll be focusing on VMware-Cisco-EMC and where these three companies converge. That means lots of exposure to Vblocks and other cool technologies that smart people in Hopkinton, San Jose, and Palo Alto are building right now as I write. Of course, I’ll be working directly with the VMware specialists on Chad’s team. If you’ve met some of these guys, you’ll know what a treat that is—there is some great talent on this team.

You might be wondering how this will affect my blogging. That was a concern that I shared while discussing this opportunity. The bottom line is that it won’t. I won’t let it. Sure, you’ll see a new disclaimer appear in the sidebar and on the About page that indicates this is a personal blog and not an EMC blog, etc., but otherwise my goal is to continue to share solid, helpful technical content with my readers. I intend to continue to provide viewpoints that are as impartial as possible, and to live up to Steve Chamber’s comments about being an anti-protocol passionista. I’m sure that I will be accused of being an EMC fanboy (that started months ago!) or a VMware fanboy, but I do aim to be as impartial and even-balanced as I possibly can be. Of course, I am human and prone to error from time to time, so don’t be too harsh on me.

To all my friends and colleagues at ePlus, it has been a tremendous pleasure working with you. Many of you I have known personally and worked with for more than ten years. It’s like we are family! I will sincerely miss your friendship and your support. ePlus is a great company with some fantastic talent, and I wish ePlus and all of you nothing but the best!

So long, status quo…

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A Bit Harsh, Don’t You Think?

Wednesday, December 23, 2009 in Virtualization by slowe | 11 comments

Yesterday, Alex Barrett of TechTarget posted a tweet about her predictions for 2010:

No wishy washy 2010 predictions from me: VMware will cut prices, and Citrix will give up on XenServer: http://bit.ly/75vDxc

The link in the tweet corresponds to this TechTarget article in which Alex predicts that VMware will cut prices and Citrix will dump XenServer and focus instead on its management products like Citrix Essentials. Citrix Essentials, as you probably know, already supports Microsoft Hyper-V. Alex’s prediction is not an unusual one; others have made this prediction before. Quite honestly, based on the progress we are seeing on XenServer’s development, I can see the logic behind Alex’s prediction.

Then along comes Simon Crosby and posts a rebuttal to Alex’s prediction, citing XenServer’s growth, industry partnerships, and projected development goals. OK, that’s fine and all; I would certainly expect Simon to be an ardent supporter of Xen and XenServer. I don’t take issue with his rebuttal; what I take issue with is this statement:

I think I’ve concluded that there are a few people whose predictions about the future I will never believe. They are precisely those who are compensated based on clicks and not insight, and who seldom take the time to check for data or accuracy.

To prevent any question of the individual about whom he was speaking, Simon added a hyperlink (recreated in the quote above) to point to Alex Barrett’s author page at TechTarget.

Ouch—that’s a bit harsh, don’t you think? It’s just bad form to say something like that about someone. First of all, a prediction isn’t exactly something you can “check for data or accuracy”; it’s a prediction. No one, including me, begrudges any vendor from defending itself. But there are ways of defending yourself without personally attacking others. There are ways to disagree respectfully and courteously. There are those out there that might want to try this approach.

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Virtualization Short Take #32

Tuesday, December 22, 2009 in Networking, Storage, Virtualization by slowe | No comments

Here it is—the last Virtualization Short Take of 2009! This is just a small collection of various virtualization-related links and articles that I’ve gathered over the last few weeks (OK, maybe more than a few weeks).

  • Scott Drummonds posted a good article with a performance comparison of thick provisioned disks vs. thin provisioned disks. This is good information and helps to clear up a lot of misinformation about the behavior of thin provisioned disks.
  • Interested in using the software iSCSI initiator with a dvSwitch and multiple paths? This article can give you the information you need to get started.
  • Frank Denneman has a great article providing some details on memory reservations and memory usage. It’s definitely worth a read, as is this post on the impact of guest OS type mismatch. See, there is a reason why it’s important to make sure you select the correct guest OS type when creating VMs.
  • I’ve written about the paravirtualized SCSI (PVSCSI) driver before, but Scott Sauer over at Virtual Insanity has a great two-part series on PVSCSI that is definitely worth a read (part 1 and part 2).
  • Although a bit dated now, Dave Lawrence has a great review of some of November’s technical white papers. He references the thin provisioning performance paper that’s also referenced in Scott Drummond’s post above, as well as a white paper on optimizing SRM performance. Thanks for bringing our attention to these documents, Dave!
  • The release of VMware View 4 brings with it PCoIP, which is supposed to bring enhanced performance over older display protocols. Unfortunately, everything I was hearing was that PCoIP was incompatible with many WAN acceleration solutions. So I was quite puzzled at this press release. Reading the press release a bit more closely, though, it would seem that Expand’s solution doesn’t actually optimize or accelerate PCoIP; rather, it enables it to be tunneled and applies Quality of Service (QoS). Something is better than nothing, I guess.
  • Rick Scherer describes a strange issue with vCenter Server 4.0 Update 1 and VMware ESXi 4.0 Update 1. Rick was seeing a number of strange symptoms, including ESXi hosts suddenly disconnecting from vCenter Server. Last time I checked Rick still hadn’t identified the root cause, although the symptoms he was seeing have since disappeared.
  • Stu provides a thorough explanation of why VMware is recommending not to install vCenter Server 4.0 Update 1 when managing VMware ESXi 4.0 hosts.
  • Need to install the HP Management Agents on VMware ESX 4.0? Here are some helpful instructions.
  • Nigel Poulton has started a great series on rack area networks (RANs), of which a key component is I/O virtualization. So far, Nigel has published part 1 (introducing the concept of a RAN), part 2 (IOV’s role in a RAN), and part 3 (IOV and hairpin turns). Part 2, in particular, has a good discussion of SR-IOV and MR-IOV. Nigel’s discussion of SR-IOV is a good complement to my own.
  • Greg Schulz also has a lengthy article on I/O virtualization.
  • Curious to know why NUMA is important with vSphere? Network Computing blogger Jake McTigue (with whom I had the honor of participating on a recent virtual networking webcast) has a good overview of NUMA and what it means for virtualized environments. It’s worth a read if you’re not already familiar with NUMA.
  • Need more information on storage alignment and VMFS block sizes? Check out this VIOPS document.

I also have a whole list of other links that I haven’t had the chance to read yet but that look like they might be interesting or useful:

A handy new addition to the Command Line Tool for View 4
Whats what in VMware View and VDI Land
How to get PCoIP with View 4 to work every time!
Revisiting the Components of the Cisco Nexus 1000v
File Virtualization… The short primer
Is Your Blade Ready for Virtualization? A Math Lesson
RSA SecureBook for VMware View hardening now publicly available!

I guess that’s enough for now. If you have any other useful, unique, or interesting virtualization-related links, feel free to share them in the comments. Thanks for reading!

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Growl Notifications with Snow Leopard Mail and Exchange

Thursday, December 10, 2009 in Macintosh, Messaging by slowe | 2 comments

Like many Mac users, I use Growl to provide customizable, centralized notifications for events occurring on my system. Rather than use the Growl team’s GrowlMail plug-in, I use a custom AppleScript that I wrote that provide new message notifications via Growl. It’s not a terribly advanced script; it just provides per-message notifications for each message received, unless I receive more than 5 messages at a time in which case the script just provides a summary notification. It’s worked very well for me for quite some time.

Now, following my upgrade to a new MacBook Pro running Snow Leopard, I’m finding that the script has an interesting flaw: when new messages are received via my Exchange account at work, the script notifies me using information from the previous message received on that account rather than the information from the newly-received message. I know that it’s not the script because notifications for all other accounts work just fine. Only the Exchange account—which uses Snow Leopard’s new Exchange support for connectivity—is affected.

Has anyone else seen this? If so, does anyone have a fix?

UPDATE: I wasn’t able to make Growl notifications invoked from an AppleScript work properly with my Exchange account, so I tried switching to GrowlMail. Unfortunately, GrowlMail has problems with Snow Leopard 10.6.2 that can only be fixed using the Terminal commands in this article. After getting GrowlMail recognized by Mail.app, notifications started appearing correctly for all accounts including my Exchange account.

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Snow Leopard, Time Machine, and Iomega ix4-200d

Wednesday, December 9, 2009 in Macintosh, Storage by slowe | 4 comments

Chad Sakac of EMC (visit his weblog here) recently sent me an Iomega ix4-200d storage unit. Considering that I didn’t need it for my VMware lab—which runs both EMC and NetApp storage arrays—I pressed it into service at home. I can’t tell you how useful it’s been, especially the built-in Time Machine support. Making my three-year-old MacBook Pro running Leopard (Mac OS X 10.5) work with the Iomega’s Time Machine implementation was a piece of cake: point it at the ix4-200d and you’re all set. It’s been great.

Recently, though, I picked up a new MacBook Pro running Snow Leopard. Unfortunately, due to some “under the covers” changes from Leopard to Snow Leopard, making your Snow Leopard-based Mac use the ix4-200d for Time Machine backups isn’t quite so straightforward. Thankfully, due to these instructions, I was able to make it work without too much effort. Here’s how.

First, you’ll need to create a sparse disk image using the following command from Terminal.app:

hdiutil create -size 500G -fs HFS+J -volname 'Time Machine' -type SPARSEBUNDLE <filename>.sparsebundle

Leopard required that the name of the sparse disk image be a concatenation of the computer’s name and the MAC address of the Ethernet interface (en0) on the system. (By the way, you have to use the MAC address of en0 even if you are performing wireless backups over en1.) It appears that Snow Leopard does not have this restriction. I followed it anyway, just in case. hdiutil will create it in whatever directory you are in when you run the command. If you aren’t in the TimeMachine directory on your ix4-200d (which would have a path of /Volumes/TimeMachine on your local Mac), then you’ll need to copy the sparse disk image later. That’s OK.

Second, you’ll need to create a file named com.apple.TimeMachine.MachineID.plist and copy that into the sparse disk image. The contents of this file should look like this:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC “-//Apple//DTD PLIST 1.0//EN” “http://www.apple.com/DTDs/PropertyList-1.0.dtd”>
<plist version=”1.0″>
<dict>
<key>com.apple.backupd.HostUUID</key>
<string>System UUID Here</string>
</dict>
</plist>

You’ll need to put your system’s UUID here; you can get this value from System Profiler. Once you’ve created this file with the appropriate values, copy it into the sparse disk image you created. I did this with the Finder and it works fine, but if you want to use Terminal.app you can use this command:

cp com.apple.TimeMachine.MachineID.plist <filename>.sparsebundle

Finally, copy—if necessary—the sparse disk image from wherever you created it to the TimeMachine share on the Iomega ix4-200d. Make sure you’ve mounted the TimeMachine share via AFP and then copy the sparsebundle over using this command:

cp -pfr <filename>.sparsebundle /Volumes/TimeMachine/<filename>.sparsebundle

After you’ve completed all these steps, you can go into the Time Machine preferences and activate Time Machine against the ix4-200d. It worked seamlessly for me on Mac OS X 10.6.2, but your mileage may vary.

I also found this site and this site helpful in confirming the necessary contents of the com.apple.TimeMachine.MachineID.plist file, which is really the key to making it work in Snow Leopard.

I hope someone finds this useful!

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