What's the difference between VMware vCenter and vSphere?

I've seen several inadequate answers to these questions recently, including those from VMware. This post is to offer clarification. 

What's the difference between VMware vCenter and vSphere?

vSphere references the suite of products, an umbrella term, of offerings by VMware of which vCenter is the centralized solution to manage many of the VMware solutions. vCenter is not vSphere, but vCenter is a component of the vSphere umbrella of vSphere products. 

What is vSphere?

vSphere is not a single sofware installation... it is a suite of products that work together to provide virtual machine and networking solutions. At a minimum, the vSphere exists when VMware vCenter and VMware ESXi are used together.

What is vCenter?

vCenter is server software that manages physical ESXi server. vCenter provides the centralized management and function vSphere offerings. At a minimum, vCenter manages ESXi servers and delivers features like vMotion, ESXi Clustering, UpdateManager, vRealize Operations Manager, NSX (Virtual Networking), and so on. VMware offers many solutions that are centrally managed within the vCenter.

vCenter is a software package on a Windows server OR a dedicated virtual appliance  running on VMware's home grown OS (called PhotonOS).

What is ESXi?

VMware ESXi is the Hypervisor which installs directly onto a physical server. ESXi abstracts the hardware and runs virtual machines. While ESXi installs directly onto computer server hardware, it is not an operating system but an abstraction layer between the Operating Systems (Windows, Linux, x86 OS architecture) and the hardware. This abstraction layer allows the Virtual Machine features & capabilities which would not otherwise exist, such as: 

• Portability  (the ability to move the operating system to different hardware platform (like moving from Dell to HP) with minimal or zero downtime. 
  
• Eliminates hardware vendor locking. 
• The Hypervisor enables multiple, different Operating Systems to run concurrently at the same time.
• Allocation of resources appropriate to the application Operating System.
• Isolation: The same hypervisor enables isolation applications and operating systems from one another even though they concurrently execute on the same computer hardware.

What is a virtual machine?

A virtual machine is a presentation of physical hardware appearing to an operating system (OS) to standardized set of hardware. To an installed OS like Windows or Linux, the virtual machine looks like a REAL MACHINE. In practice, and OS doesn't "know" it is running as a virtual machine or real machine.

Script to Get VMX File

param ($VM,
$Destination = "$pwd",
[switch]$WhatIf = $False,
[switch]$Verbose = $False )

process
{

#check if VM = pipeline
if ($_){ $VM = $_ }

#use $pwd if no -Dest

#Get VMX path\file
$vmx = Get-VM $VM | select Name,@{E={$_.ExtensionData.Config.Files.VmPathName};L="VmPathName"}

#Parse path
$vmxpath = $vmx.VmPathName.split("[")[1].split("]").trim()

#Get Datastore
$ds = get-datastore $vmxpath[0]

#Get Browse path for DIR
$vmstorepath = $ds.DatastoreBrowserPath + "\" +  ($vmxpath[1] -replace "/", "\")

Copy-DatastoreItem $vmstorepath -Verbose:$Verbose -Dest $Destination -Force -WhatIf:$WhatIf

$msg = "" | Select VM, Source, Dest, WhatIf
$msg.vm = $vm.name
$msg.Source = $vmstorepath
$msg.Dest = $Destination.trim() + "\" + ($vmxpath).split("/")[ $vmxpath.split("/").count -1 ]
$msg.WhatIf = $WhatIf
$msg

#$msg = ($Destination).trim() + "\" + ($vmxpath).split("/")[ $vmxpath.split("/").count -1 ] + $msg


}

Interesting TRICK played by AMAZON.COM

Here's the trick AMAZON plays these days. 

• CLAIM: Advertise that PRIME delivers NEXT DAY or TWO DAYS
  
• ACTUAL: Amazon deliveries in 5-7 days. 

AMAZON still claims it is PRIME 2 day delivery (or 1 day delivery) . Go lookup the current Item (or items), it still claims 24-hour, sameday,or 2-day delivery, but what I get is 5-day delivery. I'm not saying it is a scam, but you tell me?

Unique IDs for VMware virtual machines and ESXi Hosts

Virtual machines - UUID or InstanceUUID 

Historically, Unique ID's or serial numbers have been a challenge within VMware. The lack of Uniqueness limited the number of objects vCenter could manage and the inability to uniquely identify Virtual Machine utilization for asset control.

In the early days of version 3 Virtual Center, VMware virtual machines were unique identified by a managed object reference ID (called a MoREF). MoREF's were were limited to 99 instances and duplicates easily occured. vCenter 4.* came along and several changes were introduced. The Virtual Machine object history of unique identification was as follows

• Virtual Center 3 
  - MoREF's were expanded to 999, but that didn't sufficiently reduce duplicates or allow for more than 999 vm's per vCenter.
• Virtual Center 4. * 
  UuID was introduced. When a VM is created, ESXi creates the 128-bit integer Uuid such as: 421b4187-bcb4-3dc1-e7d7-c9496d3fdca9 The UUID was how vCenter 4.* tracked a Virtual Machines. This failed however, because duplicates occur during VM copy or cloning.
• vCenter 4.1 (if I recall correctly) 
  the PersistentID was introduced as a more Persistent identifier.
• vCenter 5.* - PersistentID was changed to InstanceUuid. Therefore, the InstanceUuID is, as of vCenter and ESXi version 5.0, 5.1, and 5.5 is unique. Duplicates for UUID and MOREF may still occur due to replication, copy, or cloning processes.

 

The InstanceUuid, formerly known as PersistentID before it was deprecated, is best known method for unique identification of a virtual machine within a vCenter or a collection of vCenters.

The InstanceUuid is not visible through the vCenter Client, but it is visible through the vCenter API (SDK) or through PowerCLI.

Example 

If connected to a vCenter or ESXi host through PowerCLI, here's a code snippet to view both the UuID and the PersistentID:

PowerCLI InstanceUuid Access Method

PowerCLI C:\> get-vm VirtualMachineName | get-view | % { $_.config } | Format-Table -a *uuid     Uuid                                 InstanceUuid ----                                 ------------ 421b4187-bcb4-3dc1-e7d7-c9496d3fdcb9 501b3ae4-16b3-2d7a-4492-553852f45e62

VM Example 2 - Virtual Machine List

This HTML LINK shows Virtual Machines with their InstanceUuid. The reports converts InstanceUuID to PersistentID for the support of legacy nomenclature:
Click column heading to SORT. 

Name	PersistentID	Type	State
abbott	5027322a-5e15-5a98-4c59-2927e9f9611c	VM	poweredOn
acmeascpoc01	5027ded7-b8fa-8c39-f279-a258fb183992	VM	poweredOn

  

ESXi Physical Servers

VMware's ability to obtain Serial Numbers from Physical Servers is a bit more challenging because server hardware vendors expose those attributes differently.

The object hierarchy is as follows:

$VMhost.Summary.Hardware.OtherIdentifyingInfo.IdentifierType.Key["ServiceTag"].IdentifierValue 

From a vCenter API perspective, the Powershell PowerCLI method is as follows, a simple method is as follows:

PowerCLI VMhost Serial Number

$VMhost = Get-VMhost HostName | Get-View   $VMhost.Summary.Hardware.OtherIdentifyingInfo | where {$_.IdentifierType.Key -eq "ServiceTag" } | % { $_.IdentifierValue }   [Output Values:] FOX1605G9YF FCH17307L8U

 

An code Example to get the data formatted in a nicer format follows:

Example - PowerCLI Example to get VMhost and Serial Number

PowerCLI Example to get VMhost and Serial Number

PowerCLI C:\> Get-VMhost  LabServer01 | Get-View | select name, @{N="Serial" ; E= { $_.Summar y.Hardware.OtherIdentifyingInfo | where {$_.IdentifierType.Key -eq "ServiceTag" } | % { $_.IdentifierValu e }  } }   Name           Serial ----           ------ LabServer01   {FOX1605G9YF, FCH17307L8U}

 

As shown in the example above, the code returns 2 values. This occurs because the hardware vendor, Cisco, presents serial numbers per Processor.

ALERT - BOB A. Is a secret fan of Mark Knopfler

An anonymous source stated today that Bob Apo. is a longtime fan of Mark Knopfler. Mr. Knopfler is best known for leading astray tens of millions of youth who grew up in the 70's and 80's. 

  https://duckduckgo.com/?q="mark+knopfler"

Difference between Web Client and Fat Client (and PowerCLI 'client') - vSphere 5.5

Note that VMware vSphere 5.5 VM's can be managed with VMware Workstation 10 and higher.

This article is an attempt to maintain a comparison between vCenter Web Client and the vCenter .net Client (aka, Fat Client).

Feature	.Net Client (Fat Client)	Web Client	PowerCLI
VMotion VM between Datastore AND Host at the same time	No	yes	yes
VMotion between Hosts	Yes	Yes	Yes
Vmotion Between Clusters	No	Yes	Yes
VMotion Between Datacenter	No	Yes	Yes
VMotion Between vCenters (requires Linked Mode)	No	Yes	Yes
Schedule vHardware Upgrade	No	Yes	Yes
Edit VM's with VMX-10 vHardware Supported Versions[vi]: http://kb.vmware.com/kb/2007240	No	Yes	Yes
Hot Add vCpu & vMem to VM While Power On -- Windows 2008 and lower	Yes	Yes	Yes
For Windows 2012r2	No	Yes	Yes
vCenter UpdateManager Scan	Yes	Yes	Yes
vCenter UpdateManager Patch	No	Yes	Yes
Alerts - Acknowledge and Clear	Yes	Yes	Not Native
Host Profile Creation	Yes	Yes	Yes
Host Profile Editing	Limited	Yes	Limited

 

Vmware has pretty much screwed up Host Profiles. It worked great in 4.0. Got worse with 5.0/5.1. It's no better in 5.5. The mitigating aspect of HostProfiles is that you can script away with PowerCLI most of the HostProfile frailties. That said, why use HostProfiles at all if you can standardize a VMhost configuration with scripts?

Improve and Increase VMotion Performance

1           Improve VMotion Performance

Configuring Multi-NIC vmotion in vSphere 5.5 provides much improved performance for VMOTION by creating a vmotion vmkernel for each NIC on a vswitch.  Muli-NIC vmotion began support since vSphere 5.0.  

1)      Select t vSwitch for Vmotion that contains 2 or more VMNIC utilized for vmotion.

2)      Create a VMkernel vmotion portgroup and give it the name "vmotion01″ and assign IP address on the supported VLAN.

3)      Repeat, and create a second VMkernel Interface and give it the name "vmotion02″.
The vSwitch should appear with 2 vmkernel Portgroups as follows:

Figure 8 VMotion Multiple Portgroups

4)      Per Figure 9, edit the vmotion01 NIC Teaming  tab assigning vmnic1 NIC-port as active and all others as "standby."

5)      Go to the settings of vmotion02 and configure a different NIC-port as active and all others as "standby."

vmotion01 vmnic configuration	vmotion02 vmnic configuration

 

Reference: Multi-NIC VMotion configuration: http://kb.vmware.com/kb/2007467