I’m getting some comments about the “Can’t write to device” errors. At first I thought it might be a problem with 3.5U2 since I had no problems installing the 3.5U1 on the R200, but my reinstall with 3.5U2 went without a hitch. So, here are some other ideas:

• Bad disk drive / disk drive firmware / disk related problems (I have changed from the disk delivered by Dell to a WDC 640Gig)?
• Old bios?
• Corrupted CD?
• Bad luck?

If anyone know the source of this problem, please make a comment :-)

Posted: August 29th, 2008 under Hardware, VMware by Frode.
Comments: 1

VMware isn’t very keen on sharing some of the details of ESXi, so it’s very nice that some of us virtualizing geeks are hacking their software to find new features.

One of the major problems with ESX(i) is the support for storage controllers – quite a few have discovered that their controller isn’t supported. Well, that’s a problem of the past from now on: You can just boot ESXi with PXE and still retain the configuration after reboot. You can even exploit this for making completely automatic deployment of ESXi. Kudos to Jim McCann for the guide!

Diskless ESXi: http://docs.google.com/View?docid=ddcwgcd6_4fs6s7jcf – check the buttom part to find out how you save your configuration so that it isn’t lost upon reboot :-)

Posted: August 26th, 2008 under Storage, VMware by Frode.
Comments: none

Okey, I have to admit it: I have a lot of CPU power just laying around unused. To be exact, I have around 24GHz available after my two critical hosts have gotten their share.

So, I’m testing the resource pools available for distributing resource shares to different virtual machines. The setup is pretty easy: I have a few critical hosts, namely this web server and the Windows 2003 which is running both my Windows applications and the VMware Infrastructure Server. They are both located on pentagon, a dual 3GHz machine with 7Gigs of RAM.

One of the applications that are using a lot of CPU time is SETI – Search for Extraterrestrial Intelligence – which scans the radio waves picked up with the Arecibo radio telescope. It is notorious for spending close to 100% CPU time.

To test the resource pools and VMware’s ability to distribute resources, I made two pools; the critical and the non-critical pool. The critical is getting a high amount (80%) of the CPU resources while the non-critical is getting a low amount (20%). I then created a virtual machine (linux) to host the SETI setup. This setup was then duplicated to the three hosts that I have running.

I am happy to say that the latency on the critical hosts are close to zero even though my SETI virtual machine is spending almost all the available CPU resources. The host stays at close to maximum CPU utilization at all times, wasting almost no resources.

Well, no happy story without a word of caution: Don’t add your hosts to a DRS cluster, create some resource pools, power on a number of hosts with 100% CPU utilization and then remove the DRS cluster or move one of the hosts out of it. I tried that once with my critical hosts and it quickly came to a point where everything came to a stop. And, since I’m running my virtualcenter server inside a virtual machine, it took some time before I could fix the problem again…. One lesson learned, at least :-)

The picture attached shows my current setup. The current CPU usage is 96,7%. The explanation for the low numbers on the individual CPU’s is HyperThreading which makes the resource monitor a little bit confused. No biggie, the CPU usage monitor for the host displays the right number.

Posted: August 25th, 2008 under VMware by Frode.
Comments: none

Just a quick update on the VMWare Server: The 2.0 RC2 is released and ready to be downloaded from http://www.vmware.com/beta/server/ :-)

The list of updates to this release includes support for Firefox 3 (finally…), support for SCSI pass-through devices so that you can use your tape drive in a virtual machine, disk expansion on the fly and a few other things. Nothing revolutionary, but a nice update. Maybe we will hit 2.0 RTM soon :-)

On the dark side: there’s still no support for adding VMware Server hosts to the Infrastructure server and the VIC is saying that the hardware isn’t supported… So I’ll guess that we’re still stuck with the web interface…

Posted: August 25th, 2008 under VMware by Frode.
Comments: none

So, ok, the new semester started today. As always, I’m a bit lazy on the first day so I took the opportunity to work from home instead of going to school.

It turned out be a rather ok day when I finally got out of bed. I’ve made a quick front page and a suggestion for the content in my project report. As you can read on my “Why”-page, the goal is to virtualize computer labs for students to reduce both cost and administration and at the same time deliver a better service.

After a quick look around, I chose to focus on the following virtualization solutions in the next months:

• VMware ESX/ESX(i)/Server/VDI
• Microsoft Hyper-V
• Xen
• Sun Virtualbox/xVM/Solaris Containers
• VirtualIron
• Virtuozzo
• QEMU

Are there any other solutions I should look at? I know about the different IBM/HP solutions, but they requires special hardware which are pretty expensive.

Posted: August 18th, 2008 under Hardware, Hyper-V, VMware, Xen by Frode.
Comments: 1

There have been a lot of buzz about the latest VMware bug. As always, there is nearly a competition about who screams loadest about “the big catastrophy”.

The bug, which was a time bomb left in the code after the bug testing period, make it impossible to power on new virtual machines after August 12th. Pretty stupid bug which should have been caught in Q&A, but it didn’t.

So, here are my thoughts:

• The bug did not make your virtualization solution more vulnerable for attacks from the outside. So, no security issues
• The bug did not make your servers go down unless you use VMotion, HA or DRS. So, you should probably be able to reduce the impact of the bug by turning those features off.
• VMware fixed the problem within 36 hours, as they said they would. They have also made alternative patches for those of you who can’t turn off or migrate off virtual hosts while patching.
• The bug appeared in a new release. A good sysadmin knows that all new software have bugs and delays the production phase in untill the first wave of patches have been released.

So, yeah, the bug was annoying. Yeah, it forced you to patch and reboot your ESX(i) hosts. Well, what’st he huge problem? My guess is that very few of the companies with ESX(i) hosts in production were affected by this bug. So, I just waited for the patch and used the opportunity to change from ESX to ESXi on my Poweredge 2850 :-)

Posted: August 18th, 2008 under VMware by Frode.
Comments: none

The Microsoft equivalent to VirtualCenter is named Microsoft System Center Virtual Machines Manager. The 2007 version is out while the 2008 is in beta. t should provide live migration capabilities and simplify management of large Hyper-V farms. So, it should be included in every installation of Hyper-V. But no, Microsoft, doing the same as VMware, is selling the package separately from the Windows 2008 server OS. Nice way to increase your income, not so nice for us that are on a budget…

Well, over to the snarfu:

1. The installation package is a massive 2.7GiB. VMware VirtualCenter, including MS SQL 2005, is 577MiB.
2. The system is depended upon a Active Directory Domain. Nice, another application package to administrate. I can see why you want a domain to handle user management, access control and so on, but it isn’t the most user friendly interface. And, it is extremely overkill if you only want to run virtual machines and not your entire organization on the same server farm. The virtual machine manager should be able to manage user management and access control lists on itself given an administrator account on the hosts that it should manage.
   It looks like you can add any host after installing the SCVMM on a domain host. Why you need the Active Directory is still a puzzle…
3. The SCVMM 2008 beta seems a bit unstable, to say the least. The Virtual Machine Manager keeps crashing every time I try to do something in the administration client.
4. You can actually manage VMware VirtualCenter hosts from SCVMM. I doesn’t work the other way around.

The crashing made it impossible to continue with Hyper-V. The impression I have of Hyper-V is that it is unfinished and needs a lot of polishing before it is ready for prime time. It might be an alternative for those of you who doesn’t have a virtualization solution already and depend upon the WIndows 2008 server OS for other tasks, but if you are serious about virtualization, go for VMware.

Posted: August 9th, 2008 under Hyper-V by Frode.
Comments: 1

Today I installed Windows 2008 Server Enterprise for x64. The reason for doing it was that I’m curious about Hyper-V which requires the Windows 2008 Server. It also requires a 64bit CPU with virtualization technology. The Dell PE R200 satisfies both demands and the install went well. Here are some quick thoughts:

1. Installation: It takes forever. The installation isn’t only limited to the virtualization technology. The installation is either the full version or the core version. The full version installs almost everything (you have to activate the services you want later) while the core version only installs the core services and no GUI. But, as the full server OS is quite large, the installation takes forever. The ESXi installation is done quickly, the ESX installation takes a bit more time, but the Windows 2008 takes forever. There are probably some ways of installing the Win2008 remotely and unattended, but installation is a dreadful task even if it’s automated.
2. Patching: As the server OS consists of a huge amount of services and applications, the patching also takes forever. Even though they have moved away from the Windows Update web page to a simple client, it still takes time to patch the server. You might be able to do this automaticly too, but it still takes a considerable amount of time. VMware have the VirtualCenter to do all the patching, and it does it well. And, since the footprint is really small in ESXi’ case, there aren’t really many patches to be applied.
3. Adding or modifying a network to Hyper-V could disconnect the machine from the network for a short period of time….
4. No mouse in remote desktop sessions before I install integrated services?! I have to be locally connected to install operating systems?
5. The installation of Windows 2003 Enterprise seems a bit slower than with ESX(i) even though I’m installing on a local disk drive from a local image.
6. No network card drivers installed automatically when Win2003 R2 is installed. This in addition to the mouse problem makes it hard to get Win2003 to work. The Integrated services setup requires “a newer version of Windows”…. To install Win2003 you have to manually add the “legacy network adapter” to get a network connection without the “integrated services”.
7. Really bad unix support, at least the fully supported ones. I’ll try Ubuntu and OpenSolaris later on to see if it works or not.
8. The Microsoft System Center Virtual Machines Manager 2007 download is nearly 1.7 Gigabytes. And i thought VirtualCenter was huge… Even better, the 2008 beta is close to 2.7GiB, I’m impressed :-)

To sum up my first impressions on Hyper-V: Why should I select Hyper-V instead of ESX(i) + VirtualCenter or Xen? The list of annoying things are already quite large and I expect it to be even larger when I try some of the more advanced benefits of virtualization, namly HA and live migration. In these first attempts, I haven’t found a single feature which is a real killer for the other virtualization solutions. The close connection to the Windows 2008 operating system makes it more of a competitor for VMWare Server, not ESX. And, the VMWare server is, as we already know, supported on both WIndows and Linux. And, it comes for free.

Another problem with a generalized OS as the resource manager is that it is tuned to give a good performance to all the tasks running. It might prioritize an internal operating system process before the virtual machines, giving the virtual machines less CPU time or memory even though these machines might be more critical than the host. This isn’t just a problem with Hyper-V, but with all the virtualization solutions that are available at the time. I don’t know how much this affects the virtual machines, and I guess that Microsoft have tuned Win2008 to give Hyper-V some sort of priority when it runs, but this might become an issue. Here, VMware ESX(i) have a huge advantage – the hypervisor controls all the resources.

Well, that my initial thoughts. Let’s see if it sticks after I’ve done some more tests :-)

Posted: August 8th, 2008 under Hyper-V by Frode.
Comments: 1