VMware PowerCLI 101 - Part3 - Basic VM operations

Previous posts of this blog series talked about how to install PowerCLI, connecting to ESXi host and basics of working with the vCenter server. In this article, we will go through basic VM operations.

Get basic VM details:
Get-VM -Name <name of the virtual machine>

To view all properties of a VM object:
Get-VM -Name <name of the virtual machine> | Get-Member

To start a VM:
Get-VM -Name <name of the virtual machine> | Start-VM

To restart a VM:
Get-VM -Name <name of the virtual machine> | Restart-VMGuest

To shut down a VM:
Get-VM -Name <name of the virtual machine> | Shutdown-VMGuest

To delete a VM permanently:
Get-VM -Name <name of the virtual machine> | Remove-VM -DeletePermanently

Let's have a look into the "ExtensionData" property of a virtual machine.

Status related details of a VM:
(Get-VM -Name <name of the virtual machine>).ExtensionData | select GuestHeartbeatStatus,OverallStatus,ConfigStatus

CPU, Memory config details of a VM:
(Get-VM -Name <name of the virtual machine>).ExtensionData.Config.Hardware

CPU, Memory hot add/ remove features:

Layout details of a VM:
(Get-VM -Name <name of the virtual machine>).ExtensionData.LayoutEx.File | sort Key | ft

VM tools status and other guest details:
(Get-VM -Name <name of the virtual machine>).ExtensionData.Guest

Network related info of a VM:

(Get-VM -Name <name of the virtual machine>).ExtensionData.Guest.Net

Hope this was useful. Cheers!

VMware PowerCLI 101 - Part2 - Working with vCenter server

In my previous blog, we discussed how to install PowerCLI module and connect to a stand-alone ESXi host. Now let's start with connecting to the vCenter server.

Connect-VIServer <IP of vCenter server>

Get the list of data centers present under this vCenter server: Get-Datacenter

Get the list of clusters under a datacenter: Get-Datacenter DC01 | Get-Cluster

To verify the status of HA, DRS, and vSAN of a cluster:

(Get-Cluster Cluster01) | select Name,DrsEnabled,DrsAutomationLevel,HAEnabled,HAFailoverLevel,VsanEnabled

Get the list of ESXi hosts part of a specific cluster: 

Get-Datacenter DC01 | Get-Cluster Cluster01 | Get-VMHost

To get the list of VMs hosted on a specific ESXi host:

Get-Datacenter DC01 | Get-Cluster Cluster01 | Get-VMHost 192.168.105.11 | Get-VM

To get a list of powered on and powered off VMs:

(Get-Cluster Cluster01 | Get-VM).where{$PSItem.PowerState -eq "PoweredOn"}

(Get-Cluster Cluster01 | Get-VM).where{$PSItem.PowerState -eq "PoweredOff"}

An efficient way of doing it in a single go is given below:

$vmson, $vmsoff = (Get-Cluster Cluster01 | Get-VM).where({$PSItem.PowerState -eq "PoweredOn"}, 'split')

$vmson will have the list of VMs that are PoweredOn and $vmsoff will have the list of VMs that are PoweredOff.

Cluster level inventory:

Get-Cluster | Get-Inventory

Datastore details of a cluster:

Get-Cluster | Get-Datastore | select Name, FreeSpaceGB, CapacityGB, FileSystemVersion, State

Hope this was useful. Cheers! In the next post, we will talk about performing basic VM operations using PowerCLI.

Real time VMware VM resource monitoring using PowerShell

This post is about monitoring resource usage of a list of virtual machines hosted on VMware ESXi clusters using PowerCLI. Output format is given below which gets refreshed automatically every few seconds.

Prerequisites:

• VMware.PowerCLI module should be installed on the node from which you are running the script
• You can verify using: Get-Module -Name VMware.PowerCLI -ListAvailable
• If not installed, you can find the latest version from the PSGallery: Find-Module -Name VMware.PowerCLI
• Install the module: Install-Module -Name VMware.PowerCLI

Note:

• I am using PowerCLI Version 11.0.0.10380590

Latest version of the project and code available at: github.com/vineethac/vmware_vm_monitor

Sample screenshot of output:

Notes:

VMware guidance: CPU Ready time and Co-Stop values per core greater than 5% and 3% respectively could  be a performance concern.

Hope this will be useful for resource monitoring as well as right sizing of VMs. Cheers!

References:

• http://docs.hol.vmware.com/HOL-2012/HOL-INF-04_EN/HOL-INF-04-m1/lessons/Part_1_of_4__Performance_101_-_vSphere_Performance_Basics_-_CPU__C__.html
• http://virtualization.solutions/2018/02/04/performance-monitoring-cpu/

PowerCLI to remove orphaned VM from inventory

Note: This blog has moved! New location vineethac.blogspot.com

Recently I came across a situation where one of the VM running on ESXi 6.0 was orphaned. This happened after I updated the ESXi with a patch. All the files associated with that VM was available in the datastore. But the VM was displayed in the inventory as orphaned. There was no option available to remove the VM from inventory from the web console. Inorder to register the original VMX file, the orphaned VM needs to be removed from inventory first.

Steps to resolve this issue:

1. Connect to vCenter server using PowerCLI: Connect-VIServer 192.168.14.15
2. Get list of VMs: Get-VM | Select Name

3. In my case "HCIBench_1.6.5.1_14G" was orphaned.

4. Remove the orphaned VM: Remove-VM HCIBench_1.6.5.1_14G

5. As you can see in the above screenshot, orphaned VM is removed from inventory. Now you can go to the datastore where the original VM files are stored, click on the VMX file and register (In my case, while I tried to register the VM it resulted in an error mentioning that the item already exists. I had to reboot the vCenter server to fix this issue. After rebooting the vCenter I was able to register the VMX file of the VM).

Hope it was helpful to you. Cheers!

Reference: blog.vmtraining.net

Best practices while virtualizing Microsoft SQL servers using Hyper-V

-Limit min and max memory for SQL server
-Use fixed size VHDX
-Split data and log files into separate VHDX disks
-Use multiple SCSI controllers
-Right sizing and not over allocating resources
-Making use of multiple RAID disk groups (for sequential and random access)
-For tier-1 mission critical applications use RAID 10 for data, log files, and tempDB for best performance and availability
-For lower tier SQL workloads when cost is a concern, data and tempDB can be on RAID 5
-Use of SSDs or tiered storage for higher IOPS
-If using VMQ on Hyper-V environment, on the guest OS side you can enable vRSS for processing network load across multiple CPUs
-I prefer using fixed size memory for SQL VMs
-Exclude SQL DB related files  from (*.mdf, *.ldf, *.ndf, *.bak, *.trn) on access antivirus scan
-Disable content indexing on SQL data/ log/ tempDB drives
-Enable lock pages in memory (group policy setting)
-DB IFI (Instant File Initialization)
-Set OS power plan to high performance
-OS performance options - visual effects - adjust for best performance

Hyper-V VM deployment using powershell and VHDX templates

Following powershell script can be used to deploy virtual machines on a Hyper-V host.

CODE:

#Start
#VM name
[string]$vmname = Read-Host "Name of VM"
$vmcheck = Get-VM -name $vmname

#To check for duplicate VM on the host
if(!$vmcheck)
{
Write-Host "Above warning can be ignroed as there is no duplicate VM. Please proceed and enter following details. `n"
[int32]$gen = Read-Host "Generation type"
[int32]$cpu = Read-Host "Number of vCPU"
[string]$vmpath = Read-Host "Enter path for VM configuration files (Eg: E:\VM)"
[string]$dynamic = $null

while("yes","no" -notcontains $dynamic)
{
$dynamic = Read-Host "Will this VM use dynamic memory? (yes/no)"
}

#Dynamic memory parameters
if($dynamic -eq "yes")
{
[int64]$minRAM = Read-Host "Minimum memory (MB)"
[int64]$maxRAM = Read-Host "Maximum memory (MB)"
[int64]$startRAM = Read-Host "Starting memory (MB) [Note: Specify value between $minRAM and $maxRAM]"
$minRAM = 1MB*$minRAM
$maxRAM = 1MB*$maxRAM
$startRAM = 1MB*$startRAM

#Creating the VM with dynamic RAM
New-VM -Name $vmname -Path $vmpath -Generation $gen
Set-VM -Name $vmname -DynamicMemory -MemoryStartupBytes $startRAM -MemoryMinimumBytes $minRAM -MemoryMaximumBytes $maxRAM
}

else
{
#Creating the VM with static RAM
[int64]$staticRAM = Read-Host "Static memory (MB)"
$staticRAM = 1MB*$staticRAM
New-VM -Name $vmname -Path $vmpath -Generation $gen -MemoryStartupBytes $staticRAM
}

#Setting VM auto start to none and auto stop to shutdown
Set-VM -Name $vmname -ProcessorCount $cpu -AutomaticStartAction Nothing -AutomaticStopAction ShutDown

#Creating VM hard disk directory
New-Item -path $vmpath\$vmname -name "Virtual Hard Disks" -type directory

#Enabling processor compatibility configuration for migration
Set-VMProcessor $vmname -CompatibilityForMigrationEnabled $true
}#vmcheck ends here

else
{
Write-Host "A VM named $vmname already exists"
}

#End

Now the VM is created. But it doesn't have virtual hard disk (VHDX file). Assuming that you already have a syspreped VHDX template. Copy that VHDX template to the virtual hard disk folder of the VM that you just created. Rename it as per your standard. Now attach the disk to SCSI controller if Gen 2 or to IDE controller if Gen 1. Change the boot order and select hard drive as first boot entry. Connect the NIC to vSwitch. Now you can start your VM.

Reference:

techthoughts
starwindsoftware

How Live Migration works on Hyper-V

1.Live migration setup

• Source host  creates TCP connection with destination host
• VM configuration data is transferred to destination host
• A skeleton VM is setup at destination host
• Physical memory is allocated to that VM

2.Memory pages are transferred from the source to destination host

• In-state memory (working set) of the VM will be transferred first
• Default page size is 4 KB
• All utilized pages will be copied to destination
• Modified pages are tracked by source and marked as being modified
• Several iteration of copy process will take place

3.Remaining modified pages will be transferred to destination host

• VM is then registered and the device state is transferred
• Less modified pages implies fast migration
• Total working set is copied to destination

4.Move storage handle from source to destination

• Till this step VM at destination host is not online

5.Once control of storage is transferred, VM will be online and resumed at destination

• Now the VM is completely migrated and running on destination host

6.Network cleanup

• Message is sent to physical network switch causes it to relearn MAC address of migrated VM 

VM Resource Metering

'VM Resource Metering' is a feature in Windows Server 2012 R2, which will help us to keep track of the resources consumed by virtual machines. By default this feature is disabled.

You can enable metering for a particular VM using the PowerShell command : Get-VM <virtual machine name> |  Enable-VMResourceMetering

If you want to enable it for all VMs, you can use : Get-VM | Enable-VMResourceMetering

You can view the resource usage list of all virtual machines using : Get_VM | Measure-VM

You can sort the list using : Get_VM | Measure-VM |sort AvgRAM –descending

Best practices while creating a VM on Windows Server 2012 R2 Hyper-V host