TheSaffaGeek

My ramblings about all things technical

Author Archives: Gregg Robertson


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Active Directory Web Services encountered an error while reading the settings for the specified Active Directory Lightweight Directory Services instance. Active Directory Web Services will retry this operation periodically. In the mean time, this instance will be ignored.

Yes the title is seriously long but I couldn’t think of a better title for it so used the error :).

Almost a month back now I was having the above errors in my Virtual Centre Server. Due to the need for a recent rebuild our Virtual Centre server is installed on a Windows 2008 server. The server is fine, but after going through the logs of the server I noticed the above error happening every couple of minutes, so I researched it and came across a VMware communities thread about the error but there was no real solution to it. So I scoured the web and came across the solution as it’s not a VMware error but a Windows/Microsoft error/event which “is only recorded if ADWS can’t read the ports that AD LDS is configured to use for LDAP and Secure LDAP (SSL).” The fix was on a Microsoft Active Directory blog, the last question was it exactly. I’ve posted the solution from the blog posting here:

Active Directory Web Services

Q: I’m seeing the following warning event recorded in the Active Directory Web Services event log about once a minute.

Log Name:      Active Directory Web Services
Source:        ADWS
Date:          4/8/2010 3:13:53 PM
Event ID:      1209
Task Category: ADWS Instance Events
Level:         Warning
Keywords:      Classic
User:          N/A
Computer:      corp-adlds-01.corp.contoso.com
Description:
Active Directory Web Services encountered an error while reading the settings for the specified Active Directory Lightweight Directory Services instance.  Active Directory Web Services will retry this operation periodically.  In the mean time, this instance will be ignored.
Instance name: ADAM_ContosoAddressbook

I can’t find any Microsoft resources to explain why this event occurs, or what it means.

A: Well…we couldn’t find any documentation either, but we were curious ourselves so we dug into the problem. It turns out that event is only recorded if ADWS can’t read the ports that AD LDS is configured to use for LDAP and Secure LDAP (SSL). In our test environment, we deleted those values and restarted the ADWS service, and sure enough, those pesky warning events started getting logged.

The following registry values are read by ADWS:

Key: HKLM\SYSTEM\CurrentControlSet\Services\<ADAM_INSTANCE_NAME>\Parameters
Value: Port LDAP
Type: REG_DWORD
Data: 1 – 65535 (default: 389)

Key: HKLM\SYSTEM\CurrentControlSet\Services\<ADAM_INSTANCE_NAME>\Parameters
Value: Port SSL
Type: REG_DWORD
Data: 1 – 65535 (default: 636)

Verify that the registry values described above exist and have the appropriate values. Also verify that the NT AUTHORITY\SYSTEM account has permission to read the values. ADWS runs under the Local System account.

Once you’ve corrected the problem, restart the ADWS service. If you have to recreate the registry values because they’ve been deleted, restart the AD LDS instance before restarting the ADWS service.

Thanks to Simon Long for reminding me I had this as a blog draft from over a month ago that I seem to have forgotten to post.

Gregg Robertson

*UPDATE* I’ve just had to do this fix for the latest installation of vCentre and as mentioned by people in the comments below the path is now HKLM\System\CurrentControlSet\Services\ADAM_VMwareVCMSDS\Parameters , the | SSL Port value is created as a REG_SZ instead of REG_DWORD and the value is empty. So you need to delete this and recreate it as a REG_DWORD with the value 636.


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All things virtual 13

 

Yes I decided to get rid of the roman numerals and go with the old trusty numbers from now on as I think it looks better and it’s more user friendly for the five people who read these posts 🙂

It’s been two weeks since the last All things virtual posting due to work constraints and my studying for my MCITP: Enterprise Administrator exam. Unfortunately the exam was cancelled unbeknownst to me so I’ve had to reschedule for a few weeks time (i know loads of people are going to think I just failed and don’t want to say it but I’d honestly say it if I had). Anyhow since it’s been two weeks since the last version there has been loads of really top class postings and information to have come up in the virtualisation arena.

Firstly as I said in my posting yesterday the second vBeers is happening TOMORROW,July the 1st. I was fortunate enough to have made it to the first one and it was awesome to meet and chat to loads of the guys I follow and chat to via twitter,their blogs(My blogroll holds my favourites) the VMware Community forums or in the VMware community roundtables. If you’re near the London area tomorrow evening I’d highly recommend going along.

Next is a brilliant posting by Duncan Epping of Yellow Bricks all about troubleshooting and recognising is a vm is swapping and if so how to work it out as it isn’t as simple as looking and seeing if the SWCUR value in esxtop is giving out values. As I stated in my blog posting a few weeks back I’m learning to use ESXTOP and better my skills in using this tool to manage my environments and be able to spot these kinds of things via this tool.

Eric Sloof blogged all about the release of the Maximum vSphere book. The book was written by Simon Seagrave of Techhead fame and Eric Siebert of vsphere-land.com fame. Simon wrote the chapters on ‘Performance in vSphere’ and ‘Building Your Own vSphere Lab’ and Eric wrote all the remaining chapters. John Troyer has also written the forward for the book. I haven’t personally read Eric’s VMware® VI3 Implementation and Administration book but these guys are top of the industry and their blogs are some of the best out there so you know the content is going to be amazing. Hopefully I can get my hands on a copy of this once it’s released.

As I blogged  almost a month ago now about the latest versions of vCentre and vSphere having been released, Update 2. Chad Sakac of Virtual Geek fame posted a brilliant write up all about the release also and has added some very helpful fixes to issues that may arise from updating to update 2. I’ve managed to update most of my home test environment to update 2 but unfortunately haven’t had the time to fully play with /break it yet. Talking of new versions William Lam of Virtually Ghetto fame has posted a very interesting posting all about the possible imminent release of vSphere 4.1. If rumours are true then this release will be the non COS release. Kind of crazy to put an update out then release a new version in my opinion especially for all of us that have to keep environments up to date whilst not breaking anything in the process. Jason Boche of Boche.net did a nice little posting all about how a simple Google search gives plenty of proof that the COS is going away.Duncan Epping also posted that DRS sub clusters are supposedly due tin the next version also.

A fair number of the guys and I’m friendly with and/or follow on twitter were fortunate enough to have been invited to take the VCAP-DCA beta exams over a week ago now . Jason Boche, William Lam and  Chris Dearden are a few that I noticed who blogged about it and from their comments and rants it sounds as if the exam is going to be a real test and that to pass this you are going to need to have used,played,configured and fully understand all the technologies and features that the vSphere family of products have to offer. Even though this means I’m probably going to end up spending innumerable hours playing around with my lab(which i kind of do out of nerdy fun already anyways) and also means that people can’t just learn answers to questions from cheat sites and post 500 out of 500 scores even though they misspell VMware and will hopefully also help me to increase my skills and knowledge which is what all exams/certifications should do for you.

One of the biggest banes of any VMware administrators life is the managing and controlling of snapshots especially if you allow them to be created by the users of the vm’s as i have to in our environment. I’ve posted before all about the great ways I use to ease the management and monitoring of VMware Snapshots. Last week Mike Bean posted a brilliant guest posting in the VMware communities blogs all about VMware snapshots and what they are meant for and what they are not meant for and how they are created and maintained. I’ve saved this one to my favourites as it’s got all the reasons you need to explain to a user in why they can’t have five snapshots on one vm and keep it for months on end.

Duncan Epping posted all about the new SIOC (Storage IO Control) feature due to released in most likely the next version of vSphere. I had seen this video before the posting as it was obviously all over twitter very quickly and I’m really excited and pleased that this feature is coming.

Last but not least a big congratulations to Simon Long in his announcement that he is joining VMware as a Senior Consultant. Wow if memory serves me right that takes him from being made redundant and looking for a role to being a VMware employee in 12 months!! Congrats Simon!

Gregg Robertson

 

 


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vBeers – July 1st

 

To spread the word and hopefully get as many people as possible I’m reposting Simon Seagrave’s posting about the second vBeers to be happening. I unfortunately can’t make this one due to already attending a VMware partner Exchange. Firstly a definition of vBeers:

vBeers is an informal get together of virtualisation enthusiasts and professionals to meet and discuss all things IT.  It’s a great opportunity to network, learn and meet like minded people.

clip_image001

The following is quoted from Simon’s Website:

Enjoy Talking Virtualization? Come & Socialise at vBeers!

vBeers[7]Fancy meeting up every month with other IT virtualization enthusiasts to socialise and chat over a cold beer, wine or soft-drink?  If so, then vBeers is for you!  This is a great opportunity to meet with other virtualization enthusiasts and professionals and enjoy discussing all things virtualization, and in fact anything else that comes up in conversation…

vBeers is open to everyone so whether you are a VMware vSphere, Microsoft Hyper-V, Citrix XenServer user/fan or none of the above it really doesn’t matter as “it’s all about the virtualization”.

The London vBeers meet-up is held at the lovely ole English pub, ‘The Cittie of Yorke’.  Details and directions below:

vBeers - Cittie of York
When & Where

The London vBeers is held on the first Thursday of every month starting at 6pm in ‘The Cittie of Yorke’ pub which is placed centrally to both London’s West End and The City. This venue serves a fine of selection of English beers along with soft drinks and bar snacks.

Location: The ‘Cittie of Yorke’, London

Address:  22 High Holborn, London, WC1V 6BS

Nearest Tube:  Chancery Lane

Date: First Thursday of every month

Time: 6:00pm

Ye Olde Map: (click to enlarge)

vBeers

Gregg Robertson


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Expanded disk with existing snapshot corrupted

 

Having seen a recent VMware communities posting with someone having the same problem I had I thought I’d write this up.

Almost a month back now while doing some routine maintenance on some of our then ESX3.x virtual machines we decided to expand the primary hard drive of a windows 2003 virtual machine due to it running out of space. As I’m sure you’ve guessed from the title of this posting we made the critical and very embarrassing mistake of forgetting to check if the virtual machine had a snapshot attached to it(What an idiot). Unlike vSphere, ESX3.x allows you to extend the hard drive with a snapshot attached so once we had done the extending of the drive and reattached it to the vm again (this is the way I liked to do it and I do know there are easier ways which after this problem I’ve made sure I know how to do). Once we powered the vm back up we received an error stating:

“Cannot open the disk
‘path to the .vmdk file’ or one of the snapshot disks it
depends on.
Reason: The parent virtual disk has been modified since the child was
created’

This kind of error I had seen before after cold migrating a machine with a snapshot and the CID then being different from the number in my VMDK. So I went through the steps as mentioned in this Knowledge Base article to try see if this error had anything to do with my problem.(*NB* Follow steps below before trying this)

Now as to make this posting structured to try help someone fix this problem if they have done it themselves I’m going detail the steps you should/ i myself did follow. Firstly I have to warn you that before you follow these steps I can’t promise you will get your snapshot data back nor can I promise it won’t corrupt your vm but having done this process with VMware support for this problem this is what they would make you follow also.

First is make a clone of the machine we’re trying to fix just in case

Next is the fun part due to you expanding the drive and therefore the snapshot has a different RW value than your vmdk.So you need to use putty and edit the “VirtualDisk.vmdk” file in notepad and look for

RW **number** VMFS “VirtualDisk-000001-delta.vmdk” .

 WRITE THE NUMBER AFTER RW DOWN.This one is what the drive was before the expand

Next open the “VirtualDisk.vmdk” file and look for the RW **number**  VMFS "VirtualDisk-flat.vmdk" value. What we are going to do is make it look as if the expand never happened. So edit the “VirtualDisk.vmdk” file and put in the FIRST number from the “RW **number** VMFS “VirtualDisk-000001-delta.vmdk” into the VirtualDisk-flat.vmdk line  and save it.

Secondly as I said one of the problems could be down to your CID for your VMDK being different from your snapshot/s so follow this Knowledge Base article.

After making sure the CID’s match then "delete" the snapshots. If your snapshot manager shows no snapshots(like mine did) then create one called test or whatever you like, let it create, then go to snapshot manager and click delete all and this should apply/"delete" the snapshots.

Gregg Robertson


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Understanding and using ESXTOP/RESXTOP

Lately I’ve noticed more and more people referring to stats and figures they have collected on their environments via ESXTOP/RESXTOP. I learnt about esxtop for my vcp exams but I have to be honest I haven’t really used it in my environment and recently I felt that I was surely denying myself and thereby the possible performance advantages for my environments by not using this tool to try find and fix any performance problems my vm’s/hosts may be experiencing.

I thought I would try write up a blog posting detailing everything  I had learnt but as is normally the case  some of the top bloggers out there have already beaten me to it and done such amazing jobs of it there’s no real reason for me to to do it. So instead I have collated all the information I have used to strengthen my knowledge on this tool and how it can help every virtual infrastructure administrator and or user to get the most out of their virtual machines and servers, especially with the imminent removal of the COS.

First is the ultimate resource for reference and learning what is possible with esxtop(I’m still amazed how much this tool can do and with update 2 there’s even more functionality). This VMware communities document has everything you could ever want to learn and know for esxtop and is staggeringly detailed whilst still being updated to include new functionalities and options. I’ve only managed to absorb some of the information off this document so far as it’s so much to learn and take in.

Next is a brilliant posting by Duncan Epping of Yellow Bricks fame all about the usage of ESXTOP and how he has utilised it with perfmon to retrieve all the desired data he needs for troubleshooting problems.

Jason Boche has also done a posting all about the capabilities of drilling down through the performance metrics to get very specific results.

Forbes Guthrie has done a brilliant vReference card for all the performance metrics you will see in your performance troubleshooting and monitoring. A very helpful “print out” capable card for quick reference as the same implies 🙂

Simon Long of The SLOG fame has done a very interesting posting all about using ESXTOP with VMware ESXi and is a very interesting look and example of how to do this monitoring once the COS is gone and ESXi is the only dominant host type. This kind of example is one of the main reasons I knew I needed to brush up my ESXTOP skills.

Kedrick Coleman pointed me to a very nice tool by VMware labs called ESXPlot which “is a GUI based tool that lets you explore the data collected by esxtop in batch mode”. I am yet to test this out but it looks like a very helpful tool in getting your performance data into once easy to monitor and even better to show to the boss/upper management the performance statistics of your environments/specific machines

Lastly if you were fortunate enough to attend or have a subsciption to the VMworld 2010 sessions then I would HIGHLY recommend the Troubleshooting using ESXTOP for Advanced Users session

Hopefully some of the resources help people strengthen their knowledge of ESXTOP/RESXTOP.

Gregg Robertson


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VMware Certified Advanced Professional Datacentre Administration –Blueprint Released

Just a very fast posting to notify that the blueprint for the VMware Certified Advanced Professional Datacentre Administration blueprint has been released. As I’ve said I’m really looking forward to this exam as hopefully it will enable me to differentiate myself from the multitude of vcp’s that qualified recently and hopefully also teach me and hone my skills for preparation for my VCDX someday in the future.

The Blueprint is here and it looks like a very good exam and loads of really interesting and testing things in it. I look forward to learning more about it in the coming weeks and months.

Gregg Robertson


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vCentre 4 and vSphere Update 2 Released

As of last night VMware have  released VMware vCentre 4.0 Update 2 & VMware vSphere Update 2

All the patches that were released and their build numbers are:
vCentre Server 4.0 Update 2 (Build 258672)
vSphere Client 4.0 Update 2 (Build 258672)
ESX 4.0 Update 2 (Build 261974)
VMware Tools (Build 261974)

The new features with the latest release of vSphere are:

  • Enablement of Fault Tolerance Functionality for Intel Xeon 56xx Series processors— vSphere 4.0 Update 1 supports the Intel Xeon 56xx Series processors without Fault Tolerance. vSphere 4.0 Update 2 enables Fault Tolerance functionality for the Intel Xeon 56xx Series processors.
  • Enablement of Fault Tolerance Functionality for Intel i3/i5 Clarkdale Series and Intel Xeon 34xx Clarkdale Series processors— vSphere 4.0 Update 1 supports the Intel i3/i5 Clarkdale Series and Intel Xeon 34xx Clarkdale Series processors without Fault Tolerance. vSphere 4.0 Update 2 enables Fault Tolerance functionality for the Intel i3/i5 Clarkdale Series and Intel Xeon 34xx Clarkdale Series processors.
  • Enablement of IOMMU Functionality for AMD Opteron 61xx and 41xx Series processors— vSphere 4.0 Update 1 supports the AMD Opteron 61xx and 41xx Series processors without input/output memory management unit (IOMMU). vSphere 4.0 Update 2 enables IOMMU functionality for the AMD Opteron 61xx and 41xx Series processors.
  • Enhancement of the esxtop/resxtop utility— vSphere 4.0 Update 2 includes an enhancement of the performance monitoring utilities, esxtop and resxtop. The esxtop/resxtop utilities now provide visibility into the performance of NFS datastores in that they display the following statistics for NFS datastores: Reads/s, writes/s, MBreads/s,MBwrtn/s, cmds/s, GAVG/s(guest latency).
  • Additional Guest Operating System Support— ESX/ESXi 4.0 Update 2 adds support for Ubuntu 10.04. For a complete list of supported guest operating systems with this release, see the VMware Compatibility Guide.

The new features with the latest release of vCentre are:

Guest Operating System Customization Improvements: vCenter Server now supports customization of the following guest operating systems:

  • Windows XP Professional SP2 (x64) serviced by Windows Server 2003 SP2
  • SLES 11 (x32 and x64)
  • SLES 10 SP3 (x32 and x64)
  • RHEL 5.5 Server Platform (x32 and x64)
  • RHEL 5.4 Server Platform (x32 and x64)
  • RHEL 4.8 Server Platform (x32 and 64)
  • Debian 5.0 (x32 and x64)
  • Debian 5.0 R1 (x32 and x64)
  • Debian 5.0 R2 (x32 and x64)

Check out the VMware vCentre 4 Update 2 Release Notes here and VMware vSphere Update 2 Release Notes here for all the resolved issues and all the fixes from previous bundles and how to update your environment.

You can download the latest update from the VMware download page here.

Gregg Robertson


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vExperts 2010

Firstly a massive congratulations to all who were bestowed with this accolade. In particular a massive congratulations to Barry Coombs (@VirtualisedReal) ,Gabrie van Zanten (@gabvirtualworld) ,Alan Renouf (@alanrenouf) ,Tom Howarth (@tom_howarth) ,Nick Weaver (@lynxbat) ,Eric Sloof (@esloof)  and Simon Long (@SimonLong_). Who have always been more than happy to answer any questions I have had via twitter, mail or even as recent as last night willing to power up their laptop to help with a problem we were having (Thanks again Gabrie, you’re a legend)

As I said in my last posting I didn’t have a massive amount of confidence in my being selected as a vExpert. This due to what I feel are very fair and understandable reasons and how I feel my continued efforts will hopefully help me have a much stronger case for next years. John Troyer who is the leader of the vExpert community has posted a brilliant article on the reasons some people didn’t receive it and has also given some really great pointers on how to better yourself for next years. Off of this here is some of the reasons I feel I understandably missed out and why I think I’m on the right track for next years:

  1. I only started this blog at the end of November last year so due to the award being given for the activities you did in 2009 means I did extremely little and therefore rightly so was no where near being in contention. Since then though I have made a concerted effort to post more and try bring new ideas to the community. With this blog having had almost 3000 individual views so far , 2435 of that being between January to May this year and by the views increasing by at least 200 views every month it gives me hope that I’ll be a much stronger contender for next years if I keep it up.
  2. I only started interacting with the virtualisation community late last year via twitter and was only able to attend my first VMUG end of November last year so I still need to make a name for myself and surpassing 300 followers on twitter last week of which over 98% are technical people gives me confidence that I am building a good reputation for myself among my peers and that the opinions and information I post is of interest to people in the IT field.
  3. I need to strengthen my blog postings. I’m the first to admit that my blog postings aren’t the best for a few reasons but after having read through my postings even from a few months back I can see that with each posting I feel I’ve become a lot better at it and have learnt from each one.The increased readership I feel is partly due to this refining of my skills.
  4. Plain and simple I’m either too busy or just lazy some times and due to this I haven’t been able to give back as much to the VMware communities pages and been able to join the live roundtables as much as I would like to. I plan to change this and hopefully via this be inspired to write more postings ,as one of the reasons I only post every week or so is due to the lack of good material/ideas and therefore I would rather not post up anything rather than some drivel for the sake of posting.
  5. My lack of knowledge on the many things VMware does and the technologies that are available and how they work. I only became a VCP in VI3 in September last year due to only being able to attend the pre-requisite course a few weeks before and since then I have also obtained the VCP4 accreditation within a month of it becoming available late last year and with a very nice score if i do say so myself. With this ,my knowledge on all the subjects is increasing each day and thereby my blogs can be more knowledgeable and I will have the confidence in my knowledge to write up more postings on certain subjects as the worry of any blogger is that your information is wrong and you have made a fool of yourself by giving out the wrong facts.

So if you enjoyed any of my blog postings please link the information to your friends and colleagues and even better if you link to my blog postings via your own blogs if they have helped you this is obviously a brilliant way of getting more traffic to my site and more so bringing my solutions higher in search results so that more people can be helped by them.

Congratulations to all the vExperts again and hopefully I’ll be one of you next year.

Gregg Robertson


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All things virtual XI

I’m fairly pleased that these summaries of the things that have caught my interest in virtualisation have been getting so much traffic and even more pleased is that even though I didn’t post anything massive in particular I got my highest number of viewers last month to this blog with a week still to go which is always encouraging as hopefully some of the stuff I write about helps someone like so many of the websites I read have helped me.

First is the imminent announcement of the vExperts for 2010. I would obviously be extremely honoured if I became one but I think I’d be in shock a lot more though as there are some really top people in the field.

Next is a posting by Gabrie van Zanten (@gabvirtualworld) all about the default installation settings he does when setting up a vSphere 4 host. Some of the tips he mentions are ones I never thought about or knew so I’ll definitely be referencing his posting as well as Duncan Epping’s response to Gabrie’s posting all about his best practices/recommendations. I always enjoy finding these kinds of postings as sometimes these kinds of things you only learn having done many high level environment deployments etc and are also great tips for thoughts for my builds for my future VCDX attempt.

Duncan has also done a two part blog posting with Frank Denneman all about swapping in your VMware environment and what metrics actually show performance degradation and how they are worked out. Franks posting gives more of a description on how the memory is calculated and describes the reasons for swapping happening in your environment and how to try avoid it happening and thereby impacting your servers performance.

A few people have blogged about this but the first i saw it was on Virtualization spotlight a blog by Patrick Redknap. VMware have published a video KB on how to power off an unresponsive VMware ESX virtual machine. This video is a really useful one as quite a number of times I’ve battled to get a vm to shutdown correctly even after having tried rebooting services it stayed hung.

Frank Denneman has also posted a really good posting all about setting up memory reservations in your resource pools and how they work. This posting ties in really well on the little known (at least to me and a number of people I have spoken to /asked about memory reservations) about how a vm’s reservations will hoard memory if it has been used by the virtual machine once. Frank describes it well in the part “Even if the virtual machine becomes idle, the VMkernel will not reclaim this memory and return it to the free memory set. This means that ESX can start swapping and ballooning if no free memory is available for other virtual machines while the owning VM’s aren’t using their claimed reserved memory.” Recently while doing some testing for the HA setup in my environment I noticed from a vCheck report I ran that HA stated there were no spare slots in my HA cluster, so I did some research and came across Duncan Epping’s Slot sizes posting and onto his HA deepdive posting in which he describes how the slots are worked out :

“To calculate available resources and needed resources for a fail-over HA uses a concept called “slots”. Slots dictate how many VMs can be started up before vCenter starts yelling “Out Of Resources”!! Normally each slot represents one VM.

A slot is a logical representation of the memory and CPU resources that satisfy the requirements for any powered-on virtual machine in the cluster.

In other words a slot size is the worst case CPU and Memory reservation scenario in a cluster. This directly leads to the first “gotcha”:

HA uses the highest CPU reservation of any given VM and the highest memory reservation of any given VM. If no reservations of higher than 256Mhz are set HA will use a default of 256Mhz for CPU and a default of 0MB+memory overhead for memory.

If VM1 has 2GHZ and 1024GB reserved and VM2 has 1GHZ and 2048GB reserved the slot size for memory will be 2048MB+memory overhead and the slot size for CPU will be 2GHZ. “

So I went through all of my vm’s and found a few stragglers that had memory reservations that had been switched off for a while. Once i cleared these our empty slots went from zero to 85 due to two of the switched off machines having six gb’s of ram reservations. Eric Sloof has also recently posted a great posting all about adding resource pools and how these can impact the performance of your vm’s even if you think they aren’t.

Speaking of VMware clustering options Cody Bunch has done a brilliant posting in the math behind the DRS stars. The math is a bit over my hear personally but math always has been so nothing new there. It’s very interesting how they work all these things out and a great bit of information for your setting up your DRS cluster.

Whilst i was doing my HA testing i had a few questions of how HA works and due to our environment being a test lab it’s also an integral part of our work as a consultancy so I couldn’t test what happened for the differing options you can select for HA. So I asked on twitter and Kendrick Coleman (@kendrickcoleman) not only replied to me among other people but went and tested it out for me in his test lab and posted a very nice blog posting all about it. Glad I gave him an idea and thanks for the results Kendrick!! It’s much appreciated and is one of the reasons being on twitter is priceless if you work in IT.

If you want to  comment about my blog either leave me a comment and I’ll make sure I respond to you or add my on twitter via @greggrobertson5. Also congrats to the imminently crowned vExpert’s for 2010.

Gregg Robertson