Solaris: Virtualization

Virtualization:

Virtualization means to create a virtual, or abstract, version of a physical devices or resource, such as a server, storage device, network or even operating systems, where the frame work divides the resource into one or more execution environments.


Zones:
1. A zone is a virtual environment that is created within a single running
instance of the Solaris Operating System.
2. Applications can run in an isolated and secure environment.
3. Even a privileged user in a zone cannot monitor or access process running in
a different environment.
4. Zone is a sub set of containers.
5. Runs on SPARC and X86 machines.



Containers:

1. Containers = Zones + Solaris Resource Management (SRM)

2. Container is a technology that comprises the resource management features,
such as resource pools and Solaris zones.

3. Remember Solaris containers use the same kernel.




Resource Management:
1. Is one of the integral components of Solaris 10 containers technology.
2. It allows us to do the following:
i. Allocate specific computer resources, such as CPU time & memory.
ii. Monitor how resource allocations are being used, and adjust the allocations when required.
iii. Generates more detailed accounting information.
iv. A new resource capping daemon (rcapd), regulate how much physical memory is used by a project. [Remember, a project can be a number of processes/users.]
v. Using resource management feature, multiple workloads can now be run on a single server, providing an isolated environment for each, so that one workload cannot affect the performance of the other.
vi. Resource Management feature of Solaris containers is extremely useful when a necessity of consolidating a number of applications to run on a single server.


Consolidation:
1. Reduces cost, complexity of having to manage numerous separate systems.
2. Consolidate applications onto fewer, larger, more scalable servers, and also
segregate the workload to restrict the resources that each can use.


LDOM:
1. Logical DOMain, technology allows to allocate a system’s various resources,
such as memory, CPUs & devices, into logical groupings and create multiple,
discrete system, each with their own operating system, resources, and
identify within a single computer systems.
2. Can be achieved by introducing a firmware layer.
3. Runs on SPARC based servers which supports hypervisor technology.



Additional:

Hypervisor:
1. Hypervisor is the layer between the operating system and the hardware.
2. Also called VMM (Virtual Machine Monitor), allows multiple operating systems
to run concurrently on a host computer.
3. Provides the guest operating systems with a virtual platform and monitors
the execution of the guest operating system.
4. The virtual machine approach using a hypervisor isolates failures in one
operating system from other operating systems sharing hardware.



Special Thanks to : Mr. T. Gurubalan, Sun Microsystems, My mentor for providing necessary information to blog this post.