Author Archives: Alan

About Alan

Alan Renouf has a role of Automation Frameworks Product Manager at VMware responsible for providing the architects and operators of the cloud infrastructure with the toolkits/frameworks and command-line interfaces they require to build a fully automated software-defined datacenter. Alan is a frequent blogger at http://blogs.vmware.com/vipowershell and has a personal blog at http://virtu-al.net. You can follow Alan on twitter as @alanrenouf.

New Patches for ESX Server 3.5/3i

VMware just released a whole bunch of new patches.

New patches are available for ESX Server 3.5/3i.

Please follow the instructions on the appropriate patch download page.

VMware ESX Server 3.5 Patch Download Page

ESX350-200804401-BG (Critical): Prevent DHCP from resetting the IP address and netmask when trying to acquire or renew a lease. Change the default multipath policy for all HDS modular storage arrays such as AMS, SMS, WMS, 9500V to “fixed”.

ESX350-200804402-BG (Critical): Prevent the guest from stalling for a long time during snapshot operations. Prevent the ESX Server host from crashing during snapshot consolidation. Prevent the ESX Server host from rebooting while powering on a vSMP virtual machine on a Unisys ES7000/one with eight or fewer logical CPUs. Fix emulation of instructions that access I/O ports. Fix emulation of string instructions on 64-bit guest operating systems.

ESX350-200804403-BG (Critical): Prevent hostd from crashing due to incompatible entries in /etc/vmware/hostd/authorization.xml. Allow spaces in a password while creating and editing local ESX Server users through the VI Client. Set the executable bit for .vmx configuration files. Fix a vmware-vpxa crash caused by invalid UTF-8.

ESX350-200804404-BG (General): Allow Windows virtual machines to boot when DataDigest is enabled in software iSCSI.

ESX350-200804405-BG (General): Include a megaraid2 driver fix for UNISYS platforms.

ESX350-200804406-BG (General): Add support for the Intel PRO/1000 PF Quad Port Server Adapter.

ESX350-200804407-BG (Critical): Add support for the Broadcom HT-1100 SATA/IDE controller. Prevent path thrashing during an Invista all paths down condition.

VMware ESX Server 3i Patch Download Page

ESXe350-200804401-I-BG (Critical): Fix typographic errors in the message strings of storage controller battery status, which is displayed in the VI Client. Include fixes for issues addressed by the following 3.5 patch bundles: ESX350-200804401-BG, ESX350-200804405-BG, ESX350-200804405-BG, ESX350-200804403-BG, and ESX350-200804407-BG.

We expect the next patch release in May 2008

Capacity Planning

So you have convinced the company that Virtualisation os the saviour of the IT world, you have purchased the kit and the software and the licensing, now you have no money left, how do I know what I can virtualise ?

You can either go out and spend lots of money on Capacity planning software which usually charges you per server which can get quite expensive or you can use the old fashioned way….Perfmon !

Counters should be run for at least two weeks, but preferably up to a month. The reason for this is that for most businesses, one month incorporates that company's business cycle. So, setting up counters to run for a month ensures that you capture the slow periods as well as the high use times, end of month reports etc.

Here are some counters you should consider enabling. For any of these, if the counter's resulting performance for any server is significantly higher than on other systems, it may indicate that that server won't play well when squished together with others in the virtualisation environment:

Disk\% Disk Time
If disk time is high, then that server likely does a lot of reading from and writing to its hard disk subsystem. Since virtualisation environments encapsulate whole machines into single files, a high disk time counter can mean an excess of writes to its disk file, potentially becoming a performance bottleneck.

Memory\Pages/sec
When the processor is looking for data that doesn't reside in physical RAM or when the server needs to move unused data from RAM to disk, this increases the metric for Memory\Pages/sec. A high counter here could indicate often-changing processes or workloads that require lots of dynamic data. Since the physical RAM on a virtual machine is also just a file on disk, an overly high counter here could signal a potential performance concern.

Physical Disk\Current Disk Queue Length
Related to both of the above counters, if your server is reading and writing to its disk so much that its disk subsystem cannot keep up, you will see a high Current Disk Queue Length counter. As with the previous three counters, the disk-based nature of virtualization lends itself toward the potential for disk bottlenecks. Not virtualising servers that are disk-bound may be necessary for the total performance of your virtualisation environment.

Processor\% Processor Time
The processor in each virtual server is a component of the physical processors on the host. Most of what virtualization software does is schedule physical resource use based on the needs of each virtual server. So, if you are seeing servers with a high Processor Time, then that server is constantly needing the attention of its processor. That constant need could prevent other virtual servers from getting their fair share unless you establish resource limits on the host — in the end, it slows everyone down.

System\Processor Queue Length
If you're seeing a high percentage Processor Time metric, you may also see a high Processor Queue Length metric as well. This metric deals with a processor's ability to "keep up with the load." To complicate things, it can also mean that the hardware of your physical server is not good enough to support its hosted applications. So, keep an eye on this metric.

If you see a high count for this metric, but you know your physical server is too old and slow to support its applications, you may improve performance by moving to virtualisation. But, if you see a high count on a fast server, it could indicate that that server is not the best candidate for virtualisation.

System\Context Switches/sec
A context switch is when the processor swaps out the thread that it's currently processing with another. Your processor does this all the time, as it's a part of its ability to multitask. But, when this number is very high, that's an indication of too many processes vying for attention of the processor. Where you usually see a high context switch count is on Terminal Servers or servers with very old applications. Because of the high process count on servers like Terminal Server and Citrix, they can sometimes not be good candidates for virtualisation.

System\Threads
The thread count on a system directly relates to the number of things the processor needs to accomplish. Lots of threads potentially means lots of context switches to process them all. Like with high context switches, a high thread count can also mean a well-used processor and a suspect virtualisation candidate.

Memory\Available Mbytes
Unlike the other counters, a high Available Mbytes count can be a good thing. This means that your system isn't using much of its installed RAM. Where this counter comes in handy is in right-sizing the RAM assigned to your virtual machines. Typical physical machines have too much RAM installed, which means much of it goes unused. This happens because RAM prices are cheap at the time you buy the server, but more expensive later on. So, many administrators over-spec their servers with high amounts of RAM.

In the virtualisation environment, you want to conserve RAM as much as possible so it can be used by other virtual servers. A good rule of thumb for the starting amount of RAM a virtual server needs is to subtract the amount of physical RAM from your available Mbytes and then add a little bit for breathing room. So, if you have 2GB of RAM in the server and your Available Mbytes shows 1024 megabytes, then you might start out by giving that server 1GB and working from there.

Other counters may be viable, at the end of the day it depends on your environment, these counters are just general usage.

Early Hyper-V

Microsoft confirmed Tuesday that its Hyper-V server virtualization technology is likely to ship up to a couple months ahead of the previously projected date.

The company has said all along that Hyper-V, which is currently in beta, would ship within 180 days of the release of Windows Server 2008.

The server officially launched at the end of February, and the company had tagged August as the likely ship timeframe, a full use of the 180 days.

"We are feeling pretty good that it won't be up to the full 180 days," said Dai Vu, director of virtualization products and solutions in Microsoft's server and tools division.

Last week, Larry Orecklin, general manager of the Windows enterprise and management division, said during a meeting with Network World editors that Hyper-V would ship in June or July.

Vu added that Virtual Machine Manager (VMM) 2008, which adds support for Hyper-V, would ship 30 to 60 days after Hyper-V hits its release-to-manufacturing stage. VMM 2008 is currently in beta.

When Hyper-V ships Microsoft will be adding a third hypervisor option to go along with those already available from VMware and Xen-based derivatives marketed by Citrix, Oracle, Red Hat, and Novell.

Hypervisor technology is a base technology layer that acts as the virtualization foundation for guest operating systems.

Microsoft's Hyper-V will support as guest operating systems Windows Server 2003 SP2, Novell SUSE Linux Enterprise Server 10 SP1, Windows Vista SP1 (x86) , and Windows XP SP3 (x86).

Experts believe that the hypervisor will eventually become a commodity, although VMware disputes that notion.

SCVMM 2008 – First Screenshots

System Center Virtual Machine Manager 2008 (formerly code-named “Virtual Machine Manager vNext”) was announced today at the annual Microsoft Management Summit, which enables customers to configure and deploy new virtual machines and to centrally manage their virtualized infrastructure, whether running on Windows Server 2008 Hyper-V, Microsoft Virtual Server 2005 R2 or VMware ESX Server.

Techlog has the first screenshots, taken from the Microsoft Management Summit 2008 Keynote:

SCVMM 2008: Announcement
SCVMM 2008: Overview Pane
SCVMM 2008: Virtual Center
SCVMM 2008: VMware Integration
SCVMM 2008: Host Based Rating
SCVMM 2008: HBR for VMware
SCVMM 2008: Powershell
SCVMM 2008: HA options for VM
SCVMM 2008: PRO tips

Free Citrix videos and training

f you have missed these presentations and videos from CSEIT 2007 then take a look at them. These presentation are really technical and given mostly by Citrix escalation engineers.

http://support.citrix.com/article/ctx115136

To view the CSEIT presentations and webcast recordings from the Citrix Presentation Server and Citrix NetScaler sessions, please click the appropriate presentation title.

Note: A codec may be necessary to view some of the presentations. The codec is available at http://www.gotomeeting.com/codec.

Citrix Presentation Server

• CTX115207 – CSEIT 2007 – Printer Driver Management

• CTX115208 – CSEIT 2007 – Citrix Presentation Server Health Monitoring

• CTX115192 – CSEIT 2007 – Troubleshooting Tools for a Citrix Presentation Server Environment

• CTX115204 – CSEIT 2007 – Understanding and Troubleshooting the Application Streaming in Citrix Presentation Server 4.5

• CTX115202 – CSEIT 2007 – Brief Troubleshooting Guide

• CTX115225 – CSEIT 2007 – Citrix MFCOM Programming for Administrators

• CTX115228 – CSEIT 2007 – Using and Understanding Citrix EdgeSight 4.5

• CTX115206 – CSEIT 2007 – Citrix Presentation Server 4.5 / Feature Pack 1

Citrix NetScaler

• CTX115222 – CSEIT 2007 – NetScaler Architecture, Concepts and Networking

• CTX115226 – CSEIT 2007 – Monitoring the Citrix NetScaler Application Switch

• CTX115221 – CSEIT 2007 – Command Center 3.0

• CTX115227 – CSEIT 2007 – Printer Driver Management

New angle from Microsoft Virtualisation camp

Microsoft is targeting system management as a way to differentiate itself from competitors in the virtualisation market. Anticipating that the market for virtualisation software, such as Microsoft’s Hyper-V, will eventually be commoditised, the company sees management as the key revenue opportunity, said Windows Enterprise and Management Division General Manager Larry Orecklin, speaking to reporters on Microsoft’s campus recently.

“Management becomes really the thing we believe is critical to ensuring customers can get full value from the virtualisation opportunity,” he said.

Orecklin said that for all the hype around virtualization, less than 10% of datacentres are virtualised today, according to research firm IDC. The reason for the slow adoption is that once companies began to virtualise their environments, they realised that the economics and logistics of managing them was quite difficult, he said.

Because of this, Microsoft aims to make easing management headaches the key to its virtualisation strategy rather than to battle competitors purely on the technology, Orecklin said. “Rather than either go fight for that 10%, [we’re] actually fighting for the 90%,” he said.

Microsoft has been slow to offer built-in virtualisation for its Windows Server platform, letting competitor VMware take a sizeable lead in the virtualisation market. The company had intended to release Hyper-V as part of Windows Server 2008 in February, but delayed it until six months after the OS came out because Microsoft opted to remove some originally planned features.

“I would love to have had this product out sooner,” Orecklin acknowledged about Hyper-V, which is currently available in beta as a feature of Windows Server 2008 and will be available in July in full release.

Microsoft is so keen on making management the linchpin of the virtualisation strategy that it plans to open up management for other virtualisation platforms, such as VMware and XenSource, with its Virtual Machine Manager tool, which it released last September. Virtual Machine Manager is part of Microsoft’s System Center set of datacentre management products.

The current release of Virtual Machine Manager supports only Virtual Server, Microsoft’s stand-alone virtualisation technology. Once it is released simultaneously with the full production release of Hyper-V in July, Virtual Machine Manager will support Hyper-V and VMware ESX virtualisation.

The following version of Virtual Machine Manager, the details of which have not yet been discussed publicly, will extend management to XenSource’s virtualisation product, he said.

Microsoft How-To Video – "Virtualization in Windows Server"

The session features a discussion of the virtualization technology roadmap and an outline of Microsoft's vision for how these technologies will combine with future capabilities in processors, chipsets, and I/O devices to enable unprecedented flexibility by the Windows Server platforms.

Presented by Mike Neil

Length: 51 minutes 59 seconds

 

To watch the above video please visit: Virtualization in Windows Server

Explanation of Virtual Center’s customization process

Original Article… http://www.blogit.nu/content-15.html

A while ago I was trying to work out how to change the preferences for sysprep outside the Vmware wizard so that I could put more complex items in there, the following explains the customisation process:

I was under the impression that the virtual center customisation part of the cloning process was done using Microsoft’s sysprep utility. My impression was correct with one exception … configuring the IP settings of the network cards.

On a thread there was an instance of whenever a client clone a virtual machine and tell it to join to the domain it fails ..!!
Having a look on the community it turns out that in order to make this work you need to have DHCP enabled on your network which was not the case for this client.
While most companies probably have DHCP enabled, I could not believe that vmware would make an assumption like this,
so I decided to dig a bit deeper and find out how it really works.

You may have already looked in the %program files%\Vmware\Virtual Center\Scripts directory, what you will find there are a bunch of visual basic scripts, when you open them they are encrypted using the vbscript encoder.
I decrypted the scripts, and here are my findings:

At a high level, the customisation process is as following:
Before the actual cloning of the disks start, Virtual Center will call the autoprep.wsf script. The first time it runs, it runs in a probe only mode. In Probe only mode it will validate the steps (which I will describe later) but it does not commit it any changes and deletes the files generated at the end of the process. When the validation passed succesully it will start cloning the disks and when this process is finished it will re-call the autoprep.wsf script:

  • re-creates the neccesary files (sysprep,inf, cmdlines.txt, …)
  • mounts the new disk
  • assigns a drive letter to the mounted disk
  • copies all files to the new disk
  • dismount the disk
  • and powers on the new virtual machine for the first time

What happens next depends (I will explain later) but either way eventually it will start the sysprep mini wizard. The mini-wizard will use the sysprep.inf as the answer file and if you have requested a join to domain (vmware will use the sysprep.inf file to do this), the mini-wizard will join the new Virtual Machine to the domain or .. at least it tries. As I initially expected vmware does not use the sysprep.inf file to set the static IP addresses for the NICs, so unless you have DHCP enabled the join will fail. After you clicked the error away, the mini-wizard will continue and executes the commands specified in the cmdlines.txt, it reboots virtual machine, and runs its final script to set the IP address information for each NIC!!

The process the described above counts for windows XP and Windows 2003, for Windows 2000 it does not use the sysprep.inf file to join it to the domain, instead it running an extra script joindom.bat but either way it runs it before setting the IP addresses.

Now that we have a high level overview of the process let’s have a look at the scripts and see if we can alter the process so the customization will even work for an environment where DHCP is not allowed.

As I have mentioned above at some point in the process, Virtual Center calls the autprep.wsf script to start the its customization and as I explained, it will first validate the parameters given and next it will prepare the Windows system. This is the part where it all happens:

  • It will generate a custom sysprep.inf, cmdlines.txt, setnet.cmd (used to call the setnet.wsf in order to set the IP configuration on the NICs), ..
  • Next In order to start the sysprep mini-wizards it has to copy some files and modify the registry so the virtual machine will boot the mini-wizard.
    To do this, there are two different approaches possible (I do not really know which one is used in what situation).
    • The first approach it editing the registry by mounting the hives of the image.
    • The other approach is using a trojan horse vmprep.exe.

    In the last option the %systemroot%\autochk.exe will be renamed to vmprep.cfg and copy their own %systemroot%\vmprep.exe to autochk.exe, next they will mark the image volume as dirty to make sure on its first boot the autochk.exe will get executed. This provides the process the chance to make whatever modification on the new system, more specific it will read the vmprep.dat which describes what actions it should execute, by default:

    • reset the NIC to DHCP
    • process the %systemroot%\minisetup.inf file for the registry modifications required for sysprep.
    • reboot the virtual machine

  • Next it will mount the image as a disk volume and assign it a drive letter
  • Then it will copy the following files to the new disk:
    • vmprep.exedriveletter:\Windows\System32\autochk.exe
    • vmprep.datdriveletter:\Windows\system32
    • minisetup.infdriveletter:\Windows
    • vmprep.exedriveletter:\Windows\system32
    • setupcl.exedriveletter:\Windows\System32
    • setnet.wsf driveletter:\Windows\vmware_imc
    • imc_final.bat driveletter:\Windows
    • bootrun.exedriveletter:\Windows\vmware_imc
    • setnet.batdriveletter:\Windows\vmware_imc
    • sysprep.infdriveletter:\Sysprep
    • cmdlines.txtdriveletter:\Sysprep\i386\$oem$
    • setguestinfo.wsfdriveletter:\Windows\vmware_imc

  • Power on the Virtual machine

While this process can work perfectly, it does not work if you do not allow DHCP and you have specified that you would like to join the vm to the domain, because it uses the sysprep to join the vm domain, but it only sets the IP Addresses as a post action (setnet.cmd) when the new virtual machine it completely ready .. !!