Yusuf Ozturk

You may get this error when you want to migrate a virtual machine with Live Migrate.

Check available memory (ram) on host Y. Maybe you have enough ram to pass SCVMM pre-checks but you don’t have enough to use Cluster service. Save state another virtual machine on host Y and retry migrate.

Dell Blade is a trusted virtualization solution for hosting companies. I did some benchmark tests on our Blade server (Dell PowerEdge M1000E). I used two different pyhsical servers, Dell PowerEdge M600 and Dell PowerEdge M610. Also I used two virtual machines to compare results. Server configurations:

DELL M600:
OS: Windows Server 2008 R2 (64-bit)
CPU: Intel Xeon L5430 @ 2.66GHz
Ram: 32766 MB RAM
Disk: 136GB HDD

DELL M600 VM:
OS: Windows Server 2008 R2 (64-bit)
VM CPU: Intel Xeon L5430 @ 2.66GHz
VM Ram: 4095 MB RAM
VM Disk: 40 GB, DELL EqualLogic

DELL M610:
OS: Windows Server 2008 R2 (64-bit)
CPU: Intel Xeon E5530 @ 2.40GHz
Ram: 49142 MB RAM
Disk: 136GB HDD

DELL M610 VM:
OS: Windows Server 2008 R2 (64-bit)
VM CPU: Intel Xeon E5530 @ 2.40GHz
VM Ram: 4095 MB RAM
VM Disk: 40 GB, Dell EqualLogic

Results:

I used Passmark PerformanceTest 7.0 for all benchmark tests. (http://www.passmark.com)

I got a question about ISO feature on Technet forums today.

Jan Marek:

Really good question I think. Because as I know, you can’t find it with SCVMM console. Also checking all virtual machines one by one is a way but it could be a nightmare, if you have so many virtual machines.

I wrote a Powershell script for Jan. I want to share:

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$all = Get-VM *
foreach ($i in $all)
{
$iso = $i | Get-VirtualDVDDrive | Select-Object ISO
if ($iso -like "*test*")
{
write-host VM: $i
}
}

If your ISO name is “debian.iso”, just replace “test” with “debian”.

Also if you use just “Get-ISO”, you can see all iso images on all virtual machines.

You can reach that post from here:

If we can see them with SCVMM console, please let me know.

You may get warning (13921) after migration of a virtual machine from a host to cluster:

Let’s check virtual network adapters of the virtual machine:

As you see, I have 5 network tags. But the “Internal Network” exist in the Cluster? Let’s check it.

Right click to Cluster and click to Properties. Click “Networks” tab.

Now I see only 4 network cards. So where is the “Internal Network”?

That means I don’t have any network called “Internal Network”. So I have to create Internal Network in all Clustered Hosts or I have to choose another network. I simply choose Backup Network for my virtual machine.

Tadaaaa! We fixed it :) Remember, in order to assign a virtual network to virtual machine in a cluster environment, you need to create that virtual network in all hyper-v hosts. Good luck.

You need to add secondary ip to external host? You only need to Powershell and Psexec. Psexec is a small and free program. You can download Psexec from Microsoft Technet. It works great!

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# VM Config Tool
# Created By Yusuf Ozturk
# In God We Trust, All Others We Use Powershell
 
# PsTools: http://technet.microsoft.com/en-us/sysinternals/bb897553.aspx
 
$VMName = Get-VM VDS*
 
foreach ($VM in $VMName)
{
    $IP = ($VM.Name).TrimStart('VDS00')
 
    $Server = "10.10.10." + $IP
 
    $IP1 = "10.10.11." + $IP
    $IP2 = "10.10.12." + $IP
    $IP3 = "10.10.13." + $IP
 
    $PSExecPath = "\\10.10.10.2\yusufozturk$\PsTools\psexec.exe"
 
    $Command1 = "netsh interface ipv4 add address ""Local Area Connection"" $IP1 255.255.255.0"
    $Command2 = "netsh interface ipv4 add address ""Local Area Connection"" $IP2 255.255.255.0"
    $Command3 = "netsh interface ipv4 add address ""Local Area Connection"" $IP3 255.255.255.0"
    $Command4 = "xcopy \\10.10.10.2\yusufozturk$\IIS\default.asp C:\inetpub\wwwroot\"
 
    $Shell1 = $PSExecPath + " \\" + $Server + " -u Administrator -p Password123 " + $Command1
    $Shell2 = $PSExecPath + " \\" + $Server + " -u Administrator -p Password123 " + $Command2
    $Shell3 = $PSExecPath + " \\" + $Server + " -u Administrator -p Password123 " + $Command3
    $Shell4 = $PSExecPath + " \\" + $Server + " -u Administrator -p Password123 " + $Command4
 
    cmd.exe /c $Shell1
    cmd.exe /c $Shell2
    cmd.exe /c $Shell3
    cmd.exe /c $Shell4
 
}

You need to add /c switch for cmd.exe to execute scripts in a script. You need to accept Eula of Psexec first.

You can’t remove or update vmhosts if they are in Cluster on SCVMM 2008 R2. For that reason, you have to update hosts with Powershell. If you are getting “Access Denied” message from your hosts, you can reassociate them with Powershell:

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$Credential = Get-Credential
Get-VMMManagedComputer | where {$_.State -eq "AccessDenied"} | Reassociate-VMMManagedComputer -Credential $Credential

After that, just update vmhost using SCVMM. Host will be ready.

If you install Centos 5.4 on Hyper-V R2 with Linux IC, it could hangs on reboots. We installed Linux Integration Components v2 and Linux Mouse Driver from Citrix. But we couldn’t solve the problem at the beginning.

Then I realized something, Hyper-V doesn’t support 4 CPU in Linux Machines. So I switched the CPUs 4 to 1:

And Wolaaaaa!

This solved all problems. Have fun!

You don’t need any storage server to use Hyper-V. We have Dell Blade servers and also Core i7 OEM servers. So if you have OEM servers, you have to choose VM locations carefully. Because your SATA disks will effect your virtual machines performance directly. So you have to check all SATA disks and find the best disk for the best performance. For that reason, i made this script. With VMDetails.ps1, you will always find the best SATA disk to deploy your Virtual Machine.

Also with VMDetails.PS1, you don’t need to know “Virtual Network Name” of your Hyper-V Host. If you just type “Auto”, it looks for Virtual Networks and choose the best Virtual Network Name. Also you can exclude any Virtual Network like “Backup Network”.

How about Best Hyper-V Host? Just type “Auto” for Hyper-V host name and you will get the Best Hyper-V host to deploy your virtual machines. This script looks all your hyper-v hosts and choose the best one for the best performance.

VMDetails.ps1 Preview:

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##########################
####   VMDETAILS.PS1  ####
##########################
 
# Gets Template and Hardware Details
 
function Get-VMDetails
{
param ($VMHost, $Template, $HardwareProfile, $HDDPart, $Network, $ExcludedHDD, $ExcludedNetwork)
 
    $Temp = Get-Template | Where { $_.Name -eq "$Template" }
    $OperatingSystem = $Temp.OperatingSystem.Name
    $SysprepScript = $Temp.SysprepScript.SharePath
 
    $Hardware = Get-HardwareProfile | Where { $_.Name -eq "$HardwareProfile" }
    $CpuType = $Hardware.CPUType.Name
 
    If ($VMHost -eq "Auto")
    {
        $BestServer = Get-VMHost * | Select-Object -Property Name,AvailableMemory | Sort-object AvailableMemory | Select-Object -Last 1
        $VMHostName = $BestServer.Name
        $HDDPart = $HDDPart
 
        If ($HDDPart -eq "Auto:")
        {
            $BestDisk = (Get-VMHost $VMHostName).DiskVolumes
 
            Foreach ($i in $BestDisk)
            {
                If ($i -like "$ExcludedHDD*")

You can download from here: VMDetails.ps1

Usage:

Get-VMDetails -VMHost $VMHost -Template $Template -HardwareProfile $HardwareProfile -HDDPart $HDDPart -Network $Network -ExcludedHDD $ExcludedHDD -ExcludedNetwork $ExcludedNetwork

Params:

Example:

Get-VMDetails -VMHost hyperv02 -Template W2K8R2STDT1 -HardwareProfile TEMP2GB -HDDPart Auto -Network Auto -ExcludedHDD "C:" -ExcludedNetwork "Backup Network"

How can you use results?

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$VMDetails = Get-VMDetails -VMHost "$VMHost" -Template "$VMTemplate" -HardwareProfile "$HardwareProfile" -HDDPart "$HDDPart" -Network "$NetworkName" -ExcludedHDD "$ExcludedHDDPart" -ExcludedNetwork "$ExcludedNetwork"
 
$CpuType = $VMDetails.CpuType
$OperatingSystem = $VMDetails.OperatingSystem
$SysprepScript = $VMDetails.SysprepScript
$VMHostName = $VMDetails.VMHostName
$HDDPart = $VMDetails.HDDPart
$NetworkName = $VMDetails.NetworkName

Also I updated the script. Now If you use Windows Server 2008 R2, the “Reserved System Partition” is auto excluded.

Have Fun!

Today, I tested a DELL R200 server with two different Hyper-V R2 VMs. Results are unexpectable. Hyper-V R2 beats R200 on performance test. Server configurations:

Dell R200:
OS: Windows Server 2008 R2 (64-bit)
CPU: Intel Xeon X3320 @ 2.50GHz
Ram: 4094 MB RAM
Disk Size: 232 GB, Raid1

Dell M600:
OS: Windows Server 2008 R2 (64-bit)
VM CPU: Intel Xeon L5430 @ 2.66GHz
VM Ram: 4095 MB RAM
VM Disk: 40 GB, Dell EqualLogic

Dell M610:
OS: Windows Server 2008 R2 (64-bit)
VM CPU: Intel Xeon E5530 @ 2.40GHz
VM Ram: 4095 MB RAM
VM Disk: 40 GB, Dell EqualLogic

Results:

So choosing Radore vXeon servers is a smart play for your needs :)

You may need to remove Hyper-V Host without using Credentials if you can no longer access that host. But using SCVMM panel is not a right way sometimes if that host have a associate with another SCVMM server.

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Remove-VMHost -VMHost RH-VOEM01 -Force -Confirm

With using Force switch, you can remove VMHost directly from SCVMM SQL database. So you don’t need credentials because this operation doesn’t remove SCVMM agent on target host. This command saved my life :)