vSphere Foundation and Basics

As a VMware administrator or a VMware engineer you need to have a good knowledge about the basics and the foundation components of the vSphere platform. Here I would like to compare some vSphere product versions and basic components such as port numbers, vcenter versions, requirements, etc.

This post basically targeting to the vSphere 5.5 and this post will be updating in the future. I know if you are en expert you might know about these basics but if you are a beginner it’s best place to start. 
As I explained in one of my previous post vSphere is a software suite which you can use to provide a virtualized datacenter platform to your infrastructure.  
vSphere is a per CPU socket and vRam Entitlement software suite. Basically there are three types of licences available for vCenters. 

Then What is vCenter?

vCenter is a centralized management tool that you can use to manage vmware hosts and VMs across the multiple Hosts. You can manage several features such as “High Availability (HA) , “Distributed Resource Scheduler”(DRS), Fault Tolerance (FT), Storage Distributed Resource Scheduler (SDRS), etc. We will discuss these topics in the future. 
Here I would like to compare the vSphere Standard, Enterprise and Enterprise + licences and features. (vSphere advanced is no longer available), also there are two types of vCenter editions

  • vCenter Foundation – Can manage up to 3 Hosts
  • vCenter Standard 
Enterprise +
Server Consolidation and there is no planned down time
Powerful and efficient power management
Policy based datacenter solution
Product Component
Processor Entitlement
Per 1 CPU
Per 1 CPU
Per 1 CPU
vRAM Entitlement
24 GB
32 GB
48 GB
vCPU Entitlement
8 way
8 way
32 way
SUSE Linux Enterprise Server for vmware
Cross vSwitch
Cross vSwitch
Cross vSwitch/Cross vCenters- Long distance
Storage vMotion
High Availability
Data Protection
Fault Tolerance
vShield Endpoint
vSphere Replication
Hot Add
Virtual Volumes
Storage Policy Based Managements
Big Data Extensions
Virtual Serial Port Connector
Distributed Resource Scheduler (DRS)
Distributed Power Management (DPM)
Storage DRS
Storage IO Control
Network IO Control
Flash Read Cache
Content Library
Storage APIs for Array Integration, Multipathing
Distributed Switch
Host Profiles and Auto Deploy

Minimum Requirements for vSphere 5.0 vCenter Server

  • CPU – two 64-bit CPU or one 64-bit dual-core CPU 
  • Memory – Minimum 4GB, if the database is also installed more memory will be required
  • Storage – Minimum 4GB of space required , if database is also installed more storage will be required 
  • Better performance with 1GB of network connection
  • Operating Systems :
    • Windows Server 2003 Standard, Enterprise or Datacenter 64-bit editions with SP2
    • Windows Server 2003 R2 Standard, Enterprise or Datacenter 64-bit editions with SP1
    • Windows Server 2008 Standard, Enterprise and Datacenter 64-bit Editions with SP2
    • Windows Server 2008 R2 Standard, Enterprise and Datacenter 64-bit Editions
    • Windows server 2012 
  • Microsoft .NET 3.5 SP1 Framework 
  • Microsoft Windows Installer 4.5 (If using SQL 2008 R2 Express)

Important Port Numbers for vSphere Communication 

  • 80/443 – vCenter Web Access
  • 902 – VM Heartbeat Management 
  • 8080/8443 – Web Services and HTTPS Web Services 
  • 389 – for LDAP
  • 636 – vCenter Linked mode 
  • 60099 – Web Service change service notification port
  • 10443 – vCenter Inventory Service HTTPS
  • 10109 – vCenter Inventory Service Management 
  • 10111 – vCenter Inventory Service Linked Mode Communications 

vCenter types 

Sometimes you may aware that there are two types of vCenters available 
  • Windows Based vCenter
  • SUSE Linux based vCenter Appliance (vCSA)
vCSA is a pre-configured vCenter server appliance which you can use directly in your VMware environment. If you choose to use this vCSA you don’t need to worry about the installation and configuration of the server from the scratch, all you need to do is import the server Appliance to a available host and assign an IP Address to the server. 

Positives of vCSA over the Windows based vCenter 

  • Supports to the all vCenter features (HA/DRS/SDRS/Host profiles/dVswitch)
  • No Windows licence required 
  • No OS installation to be done 
  • No vCenter installation has to be done
  • Implementing is simple and straight forward 

Negatives of vCSA over the Windows based vCenter 

  • Doesn’t support Microsoft SQL as an external database
  • vCenter Linked mode doesn’t support 
  • vCenter Heardbeat doesn’t support
  • No SingleSign-on using Windows Credentials 
  • vSphere Storage Appliance doesn’t support to this. 

Troubleshooting: Transfer Windows 2012 Core Server to 2012 GUI – Unable to find the source files

I was testing some core server configurations in my lab and I came across an issue while I was transferring windows 2012 core server to 2012 GUI.

Here I would like to share the steps that I have taken to resolve this issue with few steps. You can see complete core server configuration post later in TECHCRUMBLE, so keep reading my posts.
Here I’m not going to discuss the purpose of having a core server in your environment. I just directly dig in to the issue and I will show you the steps that I have tacken. 
You can transfer your core server to full GUI by using below command, what it actually does is install two windows features in to your cmd based core. 
Enter below commands in your cmd/Powershell to install these two windows features. 
  • Type “Import-Module ServerManager” command in your Powershell and  press “Enter”
  • Type “Install-WindowsFeature Server-Gui-Mgmt-Infra, Server-Gui-Shell -Restart” and press “Enter” on your Keyboard.
  • You can see the features start to install from the beginning   
  • Unfortunately I ended up with the below error message, here I would like to mention I have installed this server directly as a Windows Core server and I did not transfer from the GUI mode. 
  • Basically this error message says “It is unable to download the source files to continue the installation”. By default these feature installation files are located at “C:/Windows/WinSxS” folder. To resolve this issue you can mount this WinSxS folder manually to the above command to continue the installation. 
  • First of all I’m going to create a Mounting folder under C: drive and mount the “WinSxS” folder
  • Type “mkdir c:Mountdisk” – Here MountDisk is a folder name which I have chosen in my case, you can choose this name as your choice. 

  • Now attach the ISO file in to your CD-ROM (D: drive in my core server) and run “dism /mount-wim /wimfile:d:sourcesinstall.wim /index:4 /mountdir:C:MountDisk /readonly” command in your Powershell window. 
  • If you successfully performed this command you can see that the progress of the Mounting Image process 
  • Wait until it completes the Mounting Process 
  • Now perform the above feature installation command with the source of “WinSxS” folder, type “Install-WindowsFeature Server-Gui-Mgmt-Infra, Server-Gui-Shell -restart -source C:MountDiskWindowsWinSxS” and hit “Enter” to continue. 
  • After installing the features server will restart to finish the installation
  • Once the reboot completes the installation, You’re almost done. 

  • Login to the Server and see your Windows Server 2012 with GUI now.
Hope this helps you to fix your Problem…. 

Active Directory Migration from 2003 to 2012

You may aware that Microsoft has stopped supporting to the any version of  Windows 2003 from 14th of July 2015. Mainstream support ended in July 2014 and they have announced that no more Windows updates from 14th of July 2015.

If you are running with Windows 2003 servers in your datacenter you may running at a risk as there will not be any security updates for your server. So, it’s time to Migrate your old windows 2003 server to a 2012 server.

Microsoft has published several best practices to follow prior to your migration. You can follow the best practices mentioned in Migration Planing Assistant for your Migration.

Here I’m gong to show you how to Migrate two old Windows 2003 Active Directory Servers to a Windows 2012 server.


Please find the below steps for this Migration and if you are not familiar with the FSMO roles you can get the basic idea from one of my previous posts which I published regarding Flexible Single Master Operations Roles.

  • Two old Windows 2003 Active Directory Servers
    • ARW2k3AD1 – Schema , Domain Naming master 
    • ARW2k3AD2 – RID,PDC Emulator, Infrastructure Master 
  • Build a new 2012 server
  • Add this 2012 server to the domain (ARADMIGRATION.local) 
  • Raise the domain functional level of the old 2003 AD environment – Current domain functional level is Windows 2000.
  • Raise the forest functional level of the old 2003 AD environment – Current Forest functional level is Windows 2000. 
  • Add New 2012 server to the existing AD environment 
  • Replicate the AD Schema and verify 
  • Migrate the Forest Level FSMO Roles (Schema Master and Domain Naming master) to the new Server. – Test and verify. 
  • Migrate the Domain Level FSMO Roles (RID,PDC Emulator and Infrastructure Master) to the New Server – Test and Verify
  • Remove GCs from old servers
  • Demote the old 2003 servers. 
Let’s get it started:

  • Here I would like to share a command which you can use to find the FSMO servers in your AD environment. “netdom query fsmo”. Windows server 2003 does not support to this command and you need install Windows Server 2003 Service Pack 2 32-bit Support Tools , reboot the server to get this command to work. Without this support tools you can see this below error message
  • I have installed the Support Tools on the 2003 server and here is the output after the installation
  • Installed the new 2012 OS on a Server and added to the ARADMIGRATION.local domain
  • After adding to the domain and rebooting the server check the logon server by issuing “set l” command from the command prompt. The logon server is ARW2k3AD2 which is holding the Domain wide fsmo roles. 

  • In this case my current Forest and Domain function level is “Windows 2000 native”. You won’t be able to add a 2012 server to a AD environment which is holding the Windows 2000 native as the forest function level. 
  • We need to Raise the forest and Domain functional levels to Windows 2003 as we are about to add a 2012 server to our 2003 AD environment. 
  • First Raise the Domain Functional level prior to Raise the Forest functional level 
  • Open the “Active Directory Users and Computers” window and “right click” on the domain (ARADMIGRATION.local)
  • Select the “Raise Domain function level”
  • Change the Domain Functional level to “Windows Server 2003”

  • You can see the below message and click on “OK” to accept the changes, Once you made the changes you won’t be able to revert it back. 
  • You can see the below message and DCs will start to replicate the changes to all DCs. in the network. 

  • Now It’s time to raise the forest functional level. Open the “Active Directory Domains and Trusts” window and “right click” on the “Active Directory Domains and Trusts”, select the “Raise forest Functional Level”
  • You can see the current forest functional level as Windows 2000 and change it to Windows 2003.
  • You can see the below message and click “OK” to accept the changes, this change affects to the entire forest and cannot be revised. 

  • You can see the change successful message and DCs will start the replication to all the DCs in the entire forest. 

  • Now, let’s jump in to the W2k12AD server and proceed to add this server to the existing 2003 AD environment 
  • First of all , install ADDS (Active Directory Domain Services) role to this server. 
  • Launch the “Add Roles and Features” wizard and click on “Next” to continue 
  • Select the “Role-based or feature-based installation” and click next
  • Under “Server Selection” section Select the server and click on “Next” to continue. 
  • Under “Server Roles” Section Select the “Active Directory Domain Services” and click “Next”
  • You can see the “Add features window” automatically and click on “Add Features” to continue the installation.
  • Click “Next” to continue the installation 
  • At the next screen you can see the description about the “ADDS” role and click “Next” to continue. 
  • You can see the summery of the confirmation and click on “Install” to continue the installation. 
  • Wait for the installation and click “Close” after completion of the installation.
  • On your top right corner you can see a small “Yellow Exclamation mark” and once you click on that you can see an option to promote this server as a Domain Controller. (Note: No dcpromo.exe with windows 2012)
  • Once you click on the “Promote this server to a domain controller” option it will start the “Active Directory Configuration Wizard” and select the first option which you need to add a Domain Controller to an existing domain”, click next to continue.
  • In the next section you have to provide the DSRM (Directory Service Restore Mode) password. This server should be a DNS server and a GC. 

  • There is a small Message on the top once you click on the “Show more” you can see the below message. It says there is no 2008, 2008 R2 or 2012 DC in this domain. Click on “OK” to accept the Message and Click “Next” to continue to the installation
  • Here we can’t see any error and there is a warning message to say there is no old 2008, 2008 R2 or 2012 DC server in this domain network, click “Next” to continue.
  • In the next section you can see the “DNS Option” and Warning message on top of the window to say “A delegation for this DNS cannot be created….” You can safely ignore this warning message unless people in the other domains and the internet is not resolving DNS from this DNS server. Click “Next” to continue.
  • Under Additional Options You can select a specific domain controller or You can leave it as :Any Domain Controller” 
  • In this “Paths” section you can define “Database folder, Log files folder and SYSVOL folder” 
  • Under “Preparation Options” Forest and Schema preparation , Domain preparation tasks to be performed. This wizard automatically perform these tasks and all you need to do is Click on “Next”.

  • In the next section You can review the options that you have configured. Click on “Next”

  • Let this installation wizard to perform the Prerequisite check for this installation. If all the requirements selected during the installation you can see the successful message after the Prerequisite validation 

  • So far so good, Click on “Install to start the installation” 

  • Once the installation completed server will be rebooted and login to the server using Domain admin Credentials 
  • Once you logged in to the server check the FSMO roles Servers again. You don’t need any support tools to be installed on this server to perform “netdom” command. (Note: Still we did not move the server roles from old servers)
  • Replicate the AD database and check is there any replication issues. (type “Repadmin /syncall” command to replicated the database)
  • Now we are going to Migrate the FSMO roles, open the “Active Directory Users and Computers” window and right click on the domain. Select the “Operations Masters”. I believe you are familiar with this step. 

  • You can see the below Screen and check the current Operations Master Server. Here the current Operation Master Server is “ARW2k3AD2.ARADMIGRATION.local server”. We are going to Migrate the Domain wide Operations master roles to “W2k12AD.ARADMIGRATION.local” Server. Click on “Change” to move the Role. 
  • Once you click on the “Change…” you can see the below confirmation message and click on “Yes” to commit the change.
  • You can see the Confirmation message if you are successfully change the FSMO role to this server
  • Follow the same steps to Move the other Domain wide roles to new (W2k12AD) server commit the changes. 
  • Issue “netdom query fsmo” and check the FSMO roles servers. If you have successfully moved the roles you can see the changes here 
  • Open the ADDT (Active Directory Domains and Trusts) window, right click on the “Active Directory Domains and Trusts and select the “Operations Master…” option.

  • You can see the below similar window and try to identify the current Domain Naming Master

  • Click on the “Change…” to move to the new server (W2k12AD.ARADMIGRATION.local), Click on the confirmation message and see the completed message. 
  • Next we are going to move the schema master, to do this you need to perform an additional task. Here we are going to register the dynamic-link library to add the Schema master snap-in to the mmc console. To achieve this Open the “run” prompt and type “regsvr32 schmmgmt.dll” and ckick “OK”
  • You can see the Below succeeded message 
  • Now open the mmc and add the “Active Directory Schema” snap-in to the console – Follow the below steps

  • click on “OK” to continue , then you can see the added snap-in in the console 
  • Now here, the connected server is “ARW2k3AD1”, we need to change it to the “W2k12AD” server. To do this right click on the “Active Directory Schema” and select “Change Active Directory Domain Controller”. 

  • You can see the the below window and select the “W2k12AD.ARADMIGRATION.local” and click “OK”
  • You can see the below message after connecting to the Server, this server is not the Schema master and that’s the reason to get a message like this. 

  • Now right click on the “Active Directory Schema” and select the “Operations Master…”, Here you can see that I’m connected to the “W2K12AD” server.
  • Then You can see the below Window on your screen, this a similar window as you see in the previous steps. You can see the current Schema Master and the the server which you are going to move the role. 

  • Once you click on the “Change” You can see the below confirmation message

  • Once you click on the “Yes” , you can see the completed message and click “OK” to complete the task. 
  • Open a command prompt and see the current Operations Masters by issuing “netdom query fsmo” command. In my case I can see all the Operations masters moved in to the “W2k12AD” server

  • Now it’s time to change your DNS settings on other DCs and your entire domain environment, do not forget to change this in “W2k12AD” server as well.
  • After successfully changing the DNS Server IP address in your environment check the “logon server” by issuing “set l” command from one of the logged client. You may notice the changes of the logon server now. 

Remove GC (Global Catalog) and demote the old AD servers

  • As a part of the migration Process now it’s time to remove the GC and demote the old AD servers. 
  • Login to the ARW2K3AD1 server and open the “Active Directory Sites and Services” console and direct to the “NTDS settings” , right click and select “Properties”.
  • Under “NTDS Settings Properties” you can see there is a check box as a “Global Catalog”

  • Now let’s demote the old server , open “run” and type “dcpromo” to run the “Active Directory Installation Wizard”

  • Once you open the wizard click “Next” to continue 
  • At the next screen Make sure to “deselect” the “This server is the last domain controller in the domain” and click “Next”
  • Enter “Administrative Password” at the next screen and click “Next”
  • Click “Next” at the next screen 
  • This will start to remove the ADDS from this server and click on “Finish” after completion of the wizard

  • Follow the same process for the other old server as well
  • Under “Active Directory Users and Computers” verify the Domain Controllers
Now everything has been completed successfully and we have successfully Migrated old 2003 AD server to new Windows 2012 server. 
I know this is a bit long post but I wanted to show every single step which I have followed. 
Thank you for viewing my post….

Easiest way to access Windows Components : Make your life easy

 As a systems administrator or a day today end user you have to use several Windows Components to get your things done with your Windows Computer.

I believe as a general user everyone is following the same typical process to access these Windows Components after “Pressing” the “Start” key on your keyboard. I mainly focus this article for the users who are using their computers more than just to watch a movie. This article suits for the users such as Systems Administrators, System Engineers or any other people who would like to make their life easier and try to get things done in an easy way.

I know that every one is familiar with the “Run” window in Microsoft Windows Operating System

You can simply Open this window by pressing “Windows” key and “R” key together on your keyboard or Go to “Start” select “Run”.
Also there are some commands which you can run on the “CMD Prompt” which known as “CMD Commandlets” Type “CMD” on the “Run” window and it will open you a CMD Prompt.
You can use below short commands to open these Windows components easily on your computer (Please note that some commands are not working without installing the feature on your computer).   
Windows Environment Commands:
  • %ALLUSERSPROFILE% – To open the All User’s Profile
  • %HomeDrive% – To open your home drive e.g. C:
  • %UserProfile% – To open you User’s Profile
  • %temp% – To open the temporary file Folder
  • %systemroot% – To open the Windows folder
Management Consoles: 
  • eventvwr.msc –Event Viewer
  • services.msc –System Services
  • compmgmt.msc –Computer management
  • certmgr.msc –Certificate Manager
  • ciadv.msc –Indexing Service
  • devmgmt.msc –Device Manager
  • dfrg.msc –Defragment
  • diskmgmt.msc –Disk Management
  • fsmgmt.msc –Folder Sharing Management
  • gpedit.msc –Group Policy Editor 
  • lusrmgr.msc –Local Users and Groups
  • mscorcfg.msc –Net configurations
  • ntmsmgr.msc –Removable Storage
  • perfmon.msc –Performance Manager
  • secpol.msc –Local Security Policy
  • wmimgmt.msc –Windows Management
  • access.cpl –Accessibility Options
  • hdwwiz.cpl –Add New Hardware Wizard
  • appwiz.cpl –Add/Remove Programs
  • timedate.cpl –Date and Time Properties
  • desk.cpl –Display Properties
  • inetcpl.cpl –Internet Properties
  • joy.cpl –Joystick Properties
  • main.cpl keboard –Keyboard Properties
  • main.cpl –Mouse Properties
  • ncpa.cpl –Network Connections
  • ncpl.cpl –Network Properties
  • telephon.cpl –Phone and Modem options
  • powercfg.cpl –Power Management
  • intl.cpl –Regional settings
  • mmsys.cpl sounds –Sound Properties
  • mmsys.cpl –Sounds and Audio Device Properties
  • sysdm.cpl –System Properties
  • nusrmgr.cpl –User settings
  • firewall.cpl –Firewall Settings (sp2)
  • wscui.cpl –Security Center (sp2)
  • Calc –Calculator
  • Cfgwiz32 –ISDN Configuration Wizard
  • Charmap –Character Map
  • Chkdisk –Repair damaged files
  • Cleanmgr –Cleans up hard drives
  • Clipbrd –Windows Clipboard viewer
  • Cmd –Opens a new Command Window (cmd.exe)
  • Control –Displays Control Panel
  • Dcomcnfg –DCOM user security
  • Debug –Assembly language programming tool
  • Defrag –Defragmentation tool
  • Drwatson –Records programs crash & snapshots
  • Dxdiag –DirectX Diagnostic Utility
  • Explorer –Windows Explorer
  • Fontview –Graphical font viewer
  • Hostname –Returns Computer’s name (CMD Commandlet) 
  • Ipconfig –Displays IP configuration for all network adapters (CMD Commandlet)
  • Jview –Microsoft Command-line Loader for Java classes
  • MMC –Microsoft Management Console
  • Msconfig –Configuration to edit startup files
  • Msinfo32 –Microsoft System Information Utility
  • Nbtstat –Displays stats and current connections using NetBios over TCP/IP
  • Netstat –Displays all active network connections (CMD Commandlet)
  • Nslookup–Returns your local DNS server (CMD Commanlet)
  • Ping –Sends data to a specified host/IP (CMD Commandlet)
  • Regedit –Registry Editor
  • Regsvr32 –Register/de-register DLL/OCX/ActiveX
  • Regwiz -Registration wizard
  • Sfc /scannow –System File Checker
  • Sndrec32 –Sound Recorder
  • Sndvol32 –Volume control for soundcard
  • Sysedit –Edit system startup files (config.sys, autoexec.bat, win.ini, etc.)
  • Taskmgr –Task manager
  • Telnet –Telnet program (CMD Commandlet)
  • Tracert –Traces and displays all paths required to reach an internet host (CMD Commandlet)
  • Winipcfg –Displays IP configuration
  • Wupdmgr –Takes you to Microsoft Windows Update
Hope this article helps you to get your things done easy…!!!
Leave your Comments.

Introduction to Operations Master Roles

Introduction to Operations Master Roles

·         Active Directory is a Multi Master Replication System
·         There are Five Operational Roles known as “FSMO” which is stands for Flexible Single Master Operation
o   Schema Master
o   Domain Naming Master
o   RID – Relative Identifier
o   PDC Emulator
o   Infrastructure Master
·         Forest Level and Domain Level Roles
·         Schema Master – Layout or the Structure of the Data in the Active Directory Database
·         Domain Naming Master – Is used whenever add a domain to the forest or remove from the forest
·         RID Master – Responsible for allocating RID pools (SIDs)
·         PDC Emulator – Time Synchronization / most up-to-date Source
·         Infrastructure Master – Keeping changes in Object Reference consistency across domains

Installing ESXi 5.1 Hypervisor [Step-by-step]

    • Download the VMware Hypervisor from :  https://www.vmware.com/downloads
    • Mount the Downloaded ISO file to the Server (Burn it to the CD or Mount to the ILO) and boot the server
    • You will be getting the below screen 
    • Select the “ESXi-5.1.XXXXXXXX-Standard Installer” or it will start the installation automatically.
    • Continue the installation

    • You will get the below Message and Hit “Enter” to continue the installation 
    • To Accept the “End User Licence Agreement (EULA)” press “F11” and continue 
    • Installation will scan the available Hardware and will continue the installation 

    • Select the Disk to install the Hypervisor ( if you have connect a SAN you can see the remote storage volume under “Remote” ) 

    • You can view the details by pressing “F1” key 

    • Select the Keyboard Lay out in the Next step

    • Select the Root Password in for the ESXi Host and hit Enter to Continoue

    • Hypervisor will scan the system 
    • Confirm the installation by pressing “F11” 

    • Hypervisor will continue he installation 

    • After completion of the installation Hit “Enter” to reboot the system 

    • Wait until initializing the system and load the Hypervisor, you will see the below screen after completing the initialization. 

    • Press “F2” key and enter the password to customize the system and do the initial configuration. 

    • You will be redirecting to the “System Customization” page to continue the initial customization 

    • Select the “Configure Management Network” and move to “Configure Management Network”to change the IP address of the ESXi Server. 

    • Press “Enter” and select the “Set static IP address and network configuration:” option in the next window

      • You can change the IP address accordingly
      • Change the DNS settings in the same way under the DNS Configuration

      • Press “Enter” and confirm the Changes that you have made you will be redirecting to the previous page.

      • Press “ESC” key and Confirm to change the IP address

      • You can Test the Management Network connectivity by selecting “Test Management Network” option and make sure to test the physical connectivity from a local PC.

      •  Launch the “VMware vSphere Client” from your local PC and enter the login credentials of the ESXi Server

      • You can see a “Security Warning” Ignore it for the first time

      • You Will be redirecting to the ESXi home page 

      VMware vSphere and Hypervisor

      VMware vSphere is a software suite which helps you to provide a virtualization solution to Your Infrastructure. You can provide complete virtualized Infrastructure solution with this product and this is not the only solution which you can use to build your virtualized Infrastructure. Basically the base component of any virtualized environment is known as a Hypervisor. Hypervisor is the bridge between virtualized environment and the actual hardware. In VMware we call this hypervisor as “ESXi”.

      Previously this hypervisor named as ESX (Elastic Sky X) and the vmkernel is the virtualization kernel which is managed by a console operating system which is also called as Service console. The main purpose of this service console is provide a management interface to the ESX host and manage the agents. This is a linux based service console and this has been replaced by a very thin vmkernal in the ESXi version.

      VMware has developed a very thin vmkernal and they named their hypervisor as ESXi (Elastic Sky X Integrated). All the VMware management and monitoring agents can be managed by this developed vmkernal and it helped to improve the VMware capabilities. ESXi is ultra-thin architecture which is highly reliable and its small code-base allows it to be more secure with less codes to patch. ESXi use Direct Console User Interface which is known as DCUI to perform all the management tasks associated with vSphere.

      ESXi is a type 1 hypervisor – There are two types of hypervisors: type 1 hypervisor and type 2 hypervisors. ESXi is a type 1 hypervisor which is directly installed on the hardware also call it as native or bare-metal hypervisors. Hypervisors which are installed on operating systems such as VMware player, Oracle Virtual Box, Microsoft Virtual PC,etc are normally called as type 2 hypervisors or hosted hypervisors.

      Some concepts in virtualization

      Some concepts in virtualization

      Virtualization is building a virtual version of an actual entity. Basically when it comes to IT, building a software based virtual entity instead of actual entity normally we call as “Virtualize” the physical environment.
      As an example we can say that creating a Virtual Machine virtualize the physical hardware level computer, this Virtual Machine (VM) act like a real computer with an operating system.
      In Hardware level virtualization, the base PC or Server also known as “Host” is the actual hardware level computer which delivers the virtualization and the VM which we build on the Host is known as the “Guest”.
      The software which creates an environment to deliver the virtualization is known as “Hypervisor”.
      There are basically three types of Hardware Level virtualization concepts:

                 Full Virtualization – Complete Virtualized version of the actual hardware
                 Partial Virtualization – Virtualize some part of the actual hardware but not all.
                 Paravirtualization– The complete hardware level computer is not simulated, some modifications need to be done from the virtual environment

      Software-Defined Datacenter:is the foundation of the Cloud Computing. It creates the virtual version of the actual datacenter with isolated computing, storage, networking and the security resources faster than the actual Hardware level datacenter.

      I would like to compare the Advantages of the Virtual Machines and the Physical Hardware level machines.

      Physical Machine Virtual machine
      Difficult to relocate the Physical Hardware Easy to relocate: VM consists of set of files, Some “cluster features” can be used to relocate the VM. (VMotion)
      Dependent of Physical Hardware Independent of Physical Hardware
      Difficult to maintain the physical machine needs some down time Easy maintenance without a downtime: If a host needs a downtime we can use some cluster features to avoid the impact of the downtime.(VMotion)
      Limited Hardware resource in a single Machine Hardware limitation can be avoided
      Servers are Physically individual Allows servers to be consolidated and run several VMs in single host.

      Welcome to TECHCRUMBLE

      Welcome to TECHCRUMBLE

      This is my second blog and I would like to share some valuable IT related articles with internet users. If you have any suggestions, thoughts , please let me know. This is just an effort to share knowledge and effort to become an IT expert, basically here I’m focusing in to more about Microsoft and VMware related articles. So again…. let me know your suggestions and thoughts, I’m happy to accept any good or bad comments.

      This is “A SMALL STEP TO A GIANT LEAP……”

      Thank You for viewing my site…