OS Virtualization is a hot topic in the IT market.All the operating system developers and OEM are keep on introducing new virtualization technologies day by day. Have you ever asked why is it so import in infrastructure management ? Operating system virtualization very important to reduce the hardware cost and isolates the applications from server.
In older days ,if you want to port the website,you need to buy a minimum two servers hardware.One for database and another one for applications.But now just buy one good configuration server and partition it using one of the virtualization technologies
By doing this ,you are saving the space,power,money then what you want ?
Oracle offers many many virtualization technologies. We will see what type virtualization that are offered by oracle on Solaris and sun hardware.
1. Hardware virtualizations.
- Software virtualizations
Oracle is offering two type of hardware virtualization.
- Dynamic domains
(Supported in Sun M series servers like M9000,M5000 i.e sun4u architecture)
(Supported in Sun T-series serves like T5240,T5220 i.e sun4v architecture)
(Now LDOM re-branded as Oracle VM for SPARC)
You can find the architecture type using “uname –m” command from OS.
They offer electrical separation with different versions of the operating system possible per domain. The number of domains is limited per system. Dynamic System Domain features include the ability to hot plug hardware and run different versions of the Oracle Solaris Operating System per domain. Each domain can be started, stopped and rebooted independently.
|Server Model||Maximum Dynamic Domain per system|
LDOM or Oracle VM for SPARC:
The SPARC Hypervisor runs in the Hyper-Privileged execution mode, which was introduced in the sun4v architecture. In oracle VM each domains is full virtual machine which are configured with different subset of hardware. These domains can be securely live migrated between servers while running without any interruption. Like Dynamic domains,Operating systems running inside Logical Domains can be started, stopped, and rebooted independently. On the fly we can add or remove CPUs, RAM, or I/O devices without requiring a reboot. We can create 128 logical domains on these servers. Each will act as global zone.
Oracle is offering two type of software virtualization.
- Solaris Zones
- Oracle VM for X86
Solaris Zones: (Containers)
One of the most commonly using virtualization technologies on Solaris .It’s very light weight and easy to use and administrate. Oracle renamed the zones as containers and now it has meaningful name too.
“Zones + resource control = containers”. Yes. We can control the resource per zones by using rcap or dedicated method. In one Solaris global zone we can create more than 8000 zones.
There three type of zones in Solaris.
- Sparse root zone.
- Whole root zone.
- Branded zone.
Sparse root zone
The below mentioned filesystems are mounted from global zone as loop back filesystems on this zones in read only mode. So that less than 150MB free space is enough to create sparse root zone.
Whole root zone.
A self-contain zone makes copies of from the global zone and it has own /usr, /lib, /sbin and /platform directories and it will be in read/write mode. To install whole root zone we need minimum 3GB space .
One of the powerful features of Solaris 10 allows you to run Solaris 8 and 9 environments in zones, but only on SPARC. These zones are called branded zone.
Oracle VM for X86
Oracle VM is based on the open-source Xen hypervisor technology supports Windows, Linux, and Oracle Solaris. This is more over like VMware ESX server where you have base OS and to manage ESX server Vcenter will be installed on windows host.
Here you have Linux base operating system which needs to be installed as base OS on the x86 hardware.To manage these Oracle VM servers, you need to have install oracle VM application on Linux host. VM application provides a web-based portal to administrate all oracle VM servers and Guest OS.
Note:Oracle VM application uses oracle Database and weblogic software.