Vmware

 

Ø  Virtualization?

                                Virtualization is a general and ambiguous term that typically means to run multiple instances of something inside something that was intended to only run a single instance.

 Ø  How do we get virtualization?

                                  Well there is no. of options available for this, but VMware, Citrix and Microsoft are front runners in domain. Here are the products from above for the same.

Ø  VMware ESX and VMware server

Ø  Citrix Xen

Ø  Microsoft Hyper-V

Ø  VMware Server:

                  VMware Server is a free virtualization product for Microsoft Windows and Linux servers. It enables you to quickly provision new server capacity or server consolidation by partitioning a Physical server into multiple virtual machines. It is meant for those businesses who want to optimize use of their technology assets using virtualization.

Ø  Technology behind VMware Server:

• Hypervisor – 2 (Hosted Architecture)

Ø   Hosted Architecture?

                          Hosted architecture is where your virtualization software is installed as an application onto the pre-existing host operating system. This means that your virtualization layer relies on your host operating system for device support and physical resource management. VMware Server is a good example of a hosted architecture.

 

Ø  Hardware and Software support:

1. Any standard x86 compatible or x-86-64compatible personal computer
2. A wide variety of Windows, Linux, Solaris, and other guest operating systems,

Including 64-bit operating systems

3. Two-way Virtual SMP
4. Intel Virtualization Technology (Intel VT)
5. AMD-Virtualization (AMT-V)

Ø  Where VMware Server does fits for your environment?

                                      VMware server suits the requirements and demands of small and medium scale business with non-mission critical processes. It can provide following options to the business resources.

1. Virtual Machines for software development:
1. A common environment matching in both configuration and tools for your entire team
2. Quick rollout of new environments and tools
3. Archive of entire development environments for major projects

2. Virtual Machines for software testing:
1. Platform Testing with Snapshots
2. Platform Testing with Persistent and Non-persistent Disks

3. Virtual Machines for Post-release and Application-Maintenance.
1. It can create base image for you development environment
2.  Archive of the development team’s virtual machines used during the development phase
3. Rapid platform availability for quick support tasks and bug investigation

4. Run Windows, Linux, and other operating systems and applications without Software conflicts.
5. Move virtual machines from one physical host to another without having to Reconfigure them.

Ø  Features of VMware Server:

1. Web-Based Interface

                             Use VMware Infrastructure Web Access (VI Web Access) to perform host and virtual machine configuration for VMware Server 2.0.

Ø  Create, configure, and delete virtual machines

Ø  Add and remove virtual machines from the inventory

Ø  Perform power operations (start, stop, reset, suspend, and resume) on virtual Machines

Ø  Monitor the operation of virtual machines

Ø  Generate a Web shortcut to customize the VI Web Access user interface for users, with the option to limit their view to the console or a single virtual machine

Ø   Generate a VMware Remote Console desktop shortcut that allows virtual machine users to interact directly with the guest operating system outside of a Web browser

Ø  Configure host-wide VMware Server settings

2. VMware Remote Console

               VMware Remote Console enables you to interact with the guest operating system running in a virtual machine. You can run VMware Remote Console on the host or a remote client system. After you install it as a Web browser add-on from VIWeb Access, VMware Remote Console can run independently from VIWeb Access.

VMware Remote Console also allows you to connect and disconnect client CD/DVD and floppy devices.

3. Memory Support

                 The maximum amount of memory that can be allocated per virtual machine is 8GB. The amount of memory that can be used by all virtual machines combined is limited only by the amount of memory on the host computer.

4. Number of Network Adapters Supported

It can support total of 10 network adapters for a virtual machine.

5. Quiesced Backups of Virtual Machines on Windows

                          On Windows hosts, you can enable the VMware VSS Writer, which uses snapshots to maintain the data integrity of applications running inside the virtual machine when you take backups.

 

6. Support for High-Speed USB 2.0 Devices

                       If the guest operating system has the appropriate USB 2.0 device drivers, you can use peripherals that require high-speed performance, such as speakers, webcams, next-generation printers and scanners, fast storage devices, MP3 players, DVD-RW drives, and high-capacity CD-ROM jukeboxes.

Besides above there are few more such as

·         Additional host operating system support

·         Additional guest operating system support

·         improved 64 bit guest support

·         64 bit sound driver

·         Native 64 bit support on linux

·         Improved VIX-API

·         VMCI socket interface

 

Ø  Bottlenecks:

1. It puts more of your client's eggs in one basket. If the host machine breaks or needs to be taken offline, several virtual servers will go down.
2. Applications like databases that require a lot of disk activity. The prevailing wisdom is that databases should still run on dedicated physical servers.
3. Time-sensitive applications like Voice over IP (VoIP) may also be poor candidates for virtualization.
4. Virtual Machine overload: Application that are low I/O intensive and low utilization are best candidates for virtualization but need to put restriction on no. of virtual machines that can be handled with ease on physical server.

Ø  VMware Server at a glance:

Architecture	Hosted
OS Requirements	Windows or Linux
Typical Use Cases	Test & Dev, Production
Dedicated Server Required	No
Centralized Management Option	No
Ease of Use	High
Performance	Good

Ø   file Extensions?

Extension

• .log <vmname>.log or vmware.log

                      This is the file that keeps a log of key VMware Workstation activity. This file can be useful in troubleshooting if you encounter problems. This file is stored in the directory that holds the configuration (.vmx) file of the virtual machine.

• .nvram <vmname>.nvram or nvram

                      This is the file that stores the state of the virtual machine's BIOS.

• .vmdk <vmname>.vmdk

                     This is a virtual disk file, which stores the contents of the virtual machine's hard disk drive.

A virtual disk is made up of one or more .vmdk files. If you have specified that the virtual disk should be split into 2GB chunks, the number of .vmdk files depends on the size of the virtual disk. As data is added to a virtual disk, the .vmdk files grow in size, to a maximum of 2GB each. (If you specify that all space should be allocated when you create the disk, these files start at the maximum size and do not grow.) Almost all of a .vmdk file's content is the virtual machine's data, with a small portion allotted to virtual machine overhead.

                      If the virtual machine is connected directly to a physical disk, rather than to a virtual disk, the .vmdk file stores information about the partitions the virtual machine is allowed to access. Earlier VMware products used the extension .dsk for virtual disk files.

• <diskname>-<###>.vmdk

                This is a redo-log file, created automatically when a virtual machine has one or more snapshots. This file stores changes made to a virtual disk while the virtual machine is running. There may be more than one such file. The ### indicates a unique suffix added automatically by VMware Workstation to avoid duplicate file names.

• .vmsd <vmname>.vmsd

                  This is a centralized file for storing information and metadata about snapshots.

• .vmsn <vmname>-Snapshot.vmsn

                  This is the snapshot state file, which stores the running state of a virtual machine at the time you take that snapshot

• <vmname>-Snapshot<###>.vmsn

                   This is the file which stores the state of a snapshot

• .vmss <vmname>.vmss

                    This is the suspended state file, which stores the state of a suspended virtual machine.

.Some earlier VMware products used the extension .std for suspended state files

• .vmtm <vmname>.vmtm

                    This is the configuration file containing team data.

• .vmx <vmname>.vmx

                    This is the primary configuration file, which stores settings chosen in the New Virtual Machine Wizard or virtual machine settings editor. If you created the virtual machine under an earlier version of VMware Workstation on a Linux host, this file may have a .cfg extension

• .vmxf <vmname>.vmxf

                     This is a supplemental configuration file for virtual machines that are in a team. Note that the .vmxf file remains if a virtual machine is removed from the team.

• .VMDK –

                      These files are the actual hard disk of the virtual machine itself, and tend to be the largest file within the folder. You can consider the size of this file to be roughly equivalent to the size of either the disk itself (if you've chosen to use preallocated disks) or the size of the data currently stored on that disk (if you use growable disks).

• .NVRAM –

                     Consider this file the BIOS of the virtual machine.

• .VMX –

             With typically one VMX file per folder, this file holds the configuration information for the virtual machine in a text format. Unlike almost all the other files you'll see, these files can be edited using any text editing program, a process that is actually required for some functionality that is not exposed in the GUI.

• .VMXF –

                   This file, in XML format, includes additional information about the virtual machine if it has been added to a team. If a machine has been added to a team and then later removed, this file remains resident. This file can also be opened and read in a text editor.

• .VMTM –

           For virtual machines actively participating in a team, this file stores information about that team membership.

• .VMEM –

                These files, which contain a backup of the VMs paging file, are typically very small or non-existent when the virtual machine is powered off, but grow immediately to the size of configured RAM when the machine is powered on.

• .VMSN and .VMSD –

                 When snapshots are created for a virtual machine, these files are created to host the state of the virtual machine. The VMSN file stores the running state of the machine, what you could consider

the "delta" between the VMDK at the point of the snapshot and what has been processed up until the present time. The VMSD stores information and metadata about the snapshot itself.

• .VMSS -- If you've suspected the state of your machine, this file contains the suspended state of that machine. These files typically only appear when virtual machines have been suspended.

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Ø  VMWare Kernel is a Proprietary Kenral and is not based on any of the UNIX operating systems, it's a kernel developed by VMWare Company. 

 

Ø  . The VMKernel can't boot it by itself, so that it takes the help of the 3rd party operating system. In VMWare case the kernel is booted by RedHat Linux operating system which is known as service console.

 

Ø  The service console is developed based up on Redhat Linux Operating system, it is used to manage the VMKernel 

 

Ø  To restart webaccess service on vmware

service vmware-webaccess restart – this will restart apache tomcat app

 

Ø  To restart ssh service on vmware

service sshd restart

 

Ø  To restart host agent(vmware-hostd) on vmware esx server

service mgmt-vmware restart

 

Ø  Path for the struts-config.xml

/usr/lib/vmware/webAccess/tomcat/apache-tomcat-5.5.17/webapps/ui/WEB-INF/

 

Ø  To start the scripted install the command is

    esx ks=nfs:111.222.333.444:/data/KS.config ksdevice=eth0

               location                                             device name

 

Ø  Virtual Network in Simple……………….

Virtual Nic(s) on Virtual Machine(s) ----->

Physical Nic on the ESX Server (Virtual Switch - 56 Ports)  ----->

Physical Switch Port   Should be trunked with all the VLANS to which the VM's need access 

All the ESX servers should be configured with Same number of Physical Nics (vSwitches) and Connectivity also should be same, So that vMotion succeeds

All the Virtual Machines are connected to one vSwitch with Different VLANS, this means the Physical Nic(vSwitch) needs to be trunked with the same VLANS on the Physical Switch Port

 

Ø  What are the three port groups present in ESX server networking

·         Virtual Machine Port Group - Used for Virtual Machine Network

·         Service Console Port Group - Used for Service Console Communications

·         VMKernel Port Group - Used for VMotion, iSCSI, NFS Communications

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