Archive for the ‘VM’ Category

VMware Hypervisors

Posted: October 12, 2012 in ESX, VM, VMWare
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In IT, a Hypervisor, also called virtual machine manager (VMM), is one of many hardware virtualization techniques allowing multiple operating systems, termed guests, to run concurrently on a host computer. It is so named because it is conceptually one level higher than a supervisory program. The Hypervisor presents to the guest operating systems a virtual operating platform and manages the execution of the guest operating systems. Multiple instances of a variety of operating systems may share the virtualized hardware resources. Hypervisors are very commonly installed on server hardware, with the function of running guest operating systems, that themselves act as servers.

The Core of the vSphere product suite is the Hypervisor.

Hypervisor is the virtualization layer that serves as the foundation for the rest of the product line of VMware.

In the latest version of vSphere (5), the hypervisor comes in the form of VMware ESXi.

Type 1 and Type 2 Hypervisor:

Hypervisors are generally grouped into two classes: type 1 hypervisors and type 2 hypervisors. Type 1 hypervisors run directly on the system hardware and thus are often referred to as bare-metal hypervisors. Type 2 hypervisors require a host operating system, and the host operating system provides I/O device support and memory management.

VMware ESXi is a type 1 bare-metal hypervisor. (In earlier versions of vSphere, VMware ESX was also considered a type 1 bare-metal hypervisor.) Other type 1 bare-metal hypervisors include Microsoft Hyper-V and products based on the open source Xen hypervisor like Citrix XenServer and Oracle VM.


In other words, Type 1 hypervisor runs directly on the hardware; a Type 2 hypervisor runs on operating system.


This is a significant difference from earlier versions of the VMware vSphere product suite. In earlier versions of VMware vSphere, the hypervisor was available in two forms: VMware ESX and VMware ESXi. Although both products shared the same core virtualization engine, supported the same set of virtualization features, leveraged the same licenses, and were both considered baremetal installations, there were still notable architectural differences. In VMware ESX, VMware used a Linux-derived Service Console to provide an interactive environment through which users could interact with the hypervisor. The Linux-based Service Console also included services found in traditional operating systems, such as a firewall, Simple Network Management Protocol (SNMP) agents, and a web server.


Open vSwitch Configuration

Posted: October 12, 2012 in ESX, VM, VMWare
Tags: ,

Hey All,

Found the below link while browsing through the web about Open vSwitch Configuration. It is really well written by Scott Lowe…

Have a look at the below link :


  • The Service Console loses connectivity
  • Due to misconfiguration of service console, the network connection fails
  • An additional NIC is added to ESX host


To delete and recreate a virtual switch and Service Console from the command line:


  1. Run the following command to list the name of the vswif adapter:

    esxcfg-vswif -l

  2. Run the following command to delete the vswif adapter:

    esxcfg-vswif –del vswif0

  3. Run the following command to list the name of the vSwitch:

    esxcfg-vswitch -l

  4. Run the following command to delete the vSwitch:

    esxcfg-vswitch -d vSwitch0

  5. Run the following command to create the vSwitch:

    esxcfg-vswitch -a vSwitch0

  6. Run the following commands to create default port groups for vSwitch:

    esxcfg-vswitch -A “VM Network” vSwitch0
    esxcfg-vswitch -A “Service Console” vSwitch0

  7. Run the following command to create the vswif adapter:

    esxcfg-vswif –add –portgroup “Service Console” –ip=nnn.nnn.nnn.nnn –netmask= vswif0

  8. Run the following command to verify that the settings in the network file are correct:

    cat /etc/sysconfig/network


  9. Run the following commands to list all of the network adapters and associate a vmnic which has a link status of up:

    esxcfg-nics -l
    esxcfg-vswitch -L vmnic1 vSwitch0

  10. Run the following command to verify that the vmnic is associated with the vSwitch:

    esxcfg-vswitch -l

  11. Ping an IP address to check for network connectivity. If the ping fails, remove the previous vmnic from the vSwitch and try another adapter that has a link status of up.

    esxcfg-vswitch -U vmnic1 vSwitch0
    esxcfg-vswitch -L vmnic2 vSwitch0

  12. Run the following command to change the vlan ID of a vSwitch:

    [root@server root]# esxcfg-vswitch -p “VM Network 1” -v 10 vSwitch0

  13. If you make any manual changes to /etc/sysconfig/network, run the following command to restart the network service:

    service network restart

  14. Done

VM Backup – Backing up Virtual Machines with Windows Server 2008 R2 & Hyper-V


Virtual machines are basically made of files. They contain configuration files, virtual hard disks, snapshot files and saved state files. While running computers are virtual machines can benefit from virtualization, a lot of thought needs to be taken in order to protect the contents of the virtual machines and the VMs themselves, so that if something goes wrong, you can perform a pre-defined list of steps to successfully restore the VMs to a functional and running state.

Note: To install Windows Server Backup, log on to the computer by using the local Administrator account or another account with Administrator privileges. To perform backups or recoveries by using Windows Server Backup, you must be a member of the Administrators or Backup Operators groups.

Performing the backup

To perform the actual VM backup follow these steps:

1. Open Windows Server Backup from the Administrative Tools folder. In the Actions pane, click “Backup Once” (you can, of course, create a schedule for this backup).


2. In the “Backup Options” page, select “Different Options” and click Next.

3. In the “Select Backup Configuration” page, select “Custom” and click Next.

4. In the “Select Items for Backup” page, click “Add Items“.

5. In the “Select Items” window, click to select the volumes where the VM configuration files and VM hard disks are located. Also note that while it may look possible to select individual folders, do NOT select individual folders. Only select the entire volume. Failing to select the right volumes will result in a failure for the backup procedure and even if it will seem to you that all items were backed up, in fact you will not be able to restore your VMs. Click Ok.

6. Back in the “Select Items for Backup” page, click “Advanced Settings“.

7. In the “Advanced Settings” window, click to select “VSS Full Backup” and click Ok.

8. Back in the “Select Items for Backup” page, click Ok.

9. In the “Specify Destination Type” page, select the destination for the backup. I chose Local Drives, but you can also perform the backup on remote shares. Click Next.

10. In the “Select Backup Destination” page, use the drop-down list to select your destination. If you plan to backup on an external USB drive, make sure the computer recognizes it before you get to this spot. Also make sure that the destination volume contains enough free disk space for the backup to be place in. Remember that volume level backup are ALWAYS full, therefore if you’ve got 500 GB worth of VMs in one volume, you’ll need to have as much space as that (and preferably more) on your destination volume. Click Ok.

11. In the “Confirmation” page click Backup and let the backup procedure begin.

12. If you immediately switch to the Hyper-V management console, you’ll see that the VMs are being snapshotted. This is not equivalent to taking a Hyper-V snapshot, which in fact is not really a true snapshot and has nothing in relation to VSS snapshots. Because the VSS writer was registered, and because the Integration Services (Components) are installed and enabled on the VMs, they will be successfully backed up without being paused, saved or turned off. In addition, the ICs will inform the VMs that a backup procedure is taking place on the parent partition, so any VSS-aware application that is running inside the VM will also be triggered (which is very important for applications such as SQL, Exchange and so on).

13. Windows Server Backup begins to write the file(s) to disk.

14. When finished, click Close.


Backing up virtual machines can be a little different than backing up a traditional system.  Because a virtual machine is nothing more than a collection of files, it is important to be especially mindful of the backup process. One oversight along the way can mean a failed VM backup.  Hopefully this article has prepared you to backup your Virtual Machines with Hyper-V using Windows Server Backup.



Source: Petri