What is Virtualization

1.1 What is the History of Virtualization?

The concept of virtualization is generally believed to have its origins in the mainframe days in the late 1960s and early 1970s, when IBM invested a lot of time and effort in developing robust time-sharing solutions. Time-sharing refers to the shared usage of computer resources among a large group of users, aiming to increase the efficiency of both the users and the expensive computer resources they share. This model represented a major breakthrough in computer technology: the cost of providing computing capability dropped considerably and it became possible for organizations, and even individuals, to use a computer without actually owning one. Similar reasons are driving virtualization for industry standard computing today: the capacity in a single server is so large that it is almost impossible for most workloads to effectively use it. The best way to improve resource utilization, and at the same time simplify data center management, is through virtualization.
Data centers today use virtualization techniques to provide abstraction from the physical hardware, create large aggregated pools of logical resources consisting of CPUs, memory, disks, file storage, applications, networking, and offer those resources to users or customers in the form of agile, scalable, consolidated virtual machines. Even though the technology and use cases have evolved, the core meaning of virtualization remains the same: to enable a computing environment to run multiple independent systems at the same time.

1.2 Why use Virtualization?

There are many different good reasons for companies and organizations to invest in virtualization today, but it is probably safe to assume that financial motivation is number one on the list: virtualization can save a lot of money. Below is an overview of the key benefits of virtualization.
Resource optimization, Consolidation, Maximizing Uptime, Automatically Protect Applications from Server Failure, Easily Migrate Workloads as Needs Change, Protect Investment in Existing, Legacy Systems.

1.3 What are Hypervisors?

If virtualization is defined as enabling multiple operating systems to run on a single host computer, then the essential component in the virtualization stack is the hypervisor. This hypervisor, also called Virtual Machine Monitor (VMM), creates a virtual platform on the host computer, on top of which multiple guest operating systems are executed and monitored. This way, multiple operating systems, which are either multiple instances of the same operating system, or different operating systems, can share the hardware resources offered by the host.
native or bare metal

Native hypervisors are software systems that run directly on the host's hardware to control the hardware, and to monitor the guest operating systems. Consequently, the guest operating system runs on a separate level above the hypervisor. Examples of this classic implementation of virtual machine architecture are Oracle VM, Microsoft Hyper-V, VMware ESXi and Xen.

Hosted
Hosted hypervisors are designed to run within a traditional operating system. In other words, a hosted hypervisor adds a distinct software layer on top of the host operating system, and the guest operating system becomes a third software level above the hardware. A well-known example of a hosted hypervisor is Oracle VM VirtualBox. Others include VMware Server and Workstation, Microsoft Virtual PC, KVM, QEMU and Parallels.

1.4 What Features Does Oracle VM Provide?

This section gives an overview of the Oracle VM Manager features used to manage Oracle VM Servers, virtual machines, storage repositories, networks, and resources. Oracle VM Manager provides the following main capabilities:

·         Manages the physical Oracle VM Servers and can, for example, reboot or rediscover the physical hardware.

·         Creates and configures server pools.

·         Creates and manages Oracle VM Server logical networks, for example, NIC port bonding, and configuring VLAN networks.

·         Manages storage devices such as local disks, SAN storage and Network File Servers.

·         Creates and manages storage repositories.

·         Manages resources, including ISO files, virtual machine templates, virtual machine images, and virtual machine assemblies.

·         Manages the virtual machines. This includes creating virtual machines from either installation media or from templates, starting, logging in, shutting down, and deleting virtual machines.

·         Imports, clones and migrates virtual machines.

·         Performs load balancing of virtual machines in server pools.

·         Manages jobs in the Oracle VM environment.

·         Manages policies such as High Availability, Distributed Resource Scheduling, and Distributed Power Management.

IGNITE BACKUP --- HP_UNIX

IGNITE BACKUP

HP-UX have a software to back up the OS called "Ignite" . It bundled with OS installed. The easy way to make a OS backup is using tape data cartridge. just plug the tape and run command "make_tape_recovery -AI". To restore OS using recovery tape.

Command : make_tape_recovery –AI

Ignite unix releases are available to install the HP-UX 10.01,10.10,10.20,11.0 and 11i releases.

Required Bundle: Ignite bundle

To identifying the source bundle

#swlist | grep –I ignite

#swlist –a install source –l bundle

To verify tape Hardware Path:

# Ioscan –funC tape

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To Create the bootable recovery tape:

Backing up the complete root VG using the default device file  /dev/rmt/0mn

# /opt/ignite/bin/make_tape_recovery –Av –C –d /dev/rmt/0m

-A  based on the files thet are specified for inclusion, this option identifies the disks and VG’s in the archieve.

-v verbose mode

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

To Backing up the complete root VG using a non-default device file.

# /opt/ignite/bin/make_tape_recovery –Av –a /dev/rmt/c6t0d1BESTn

Verify the make_tape_recovery Tape Looking up the files

/var/opt/ignite/recovery

NIS client setup on Linux

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