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Oracle VM for X86 basic concepts

Terms in this set (70)

Types of Virtualization
Hardware Partitioning
OS Partitioning
Host Based Hypervisor
Bare Metal Hypervisor
Hardware Partitioning
With HW partitioning we slice the server into several isolated components (cpu, power supply, storage, etc). The bus server is splitted into a logical way, so is presented to the OS as a specific hardware unit.
Example of this architecture are the M5, M6 , E6500 Sparc Lines of servers

Some benefits
- High Isolation
- Different OS versions

Some disadvantages
- Expensive and propietary hardware
OS Partitioning
With OS partitioning we can have moderate isolation and similar OS versions installed.
The guest domains share the OS kernel and some common OS resources
One examples of this technologies are Solaris Containers/Zones and FreeBSD Jails. They offer scalability at an affordable price, not so tied to hardware arquitecture
Host Based Hypervisor
A software layer is added to the OS, to handle with the guest domains. It's easy to use , primary used on desktops (Vmware Workstation. Mac Parallels, Virtualbox, among others). Useful for simulations.

Provides a poor performance
BareMetal Hypervisor
In this type of VM, the server run a small bootable OS with a form of Hypervisor (Xen Hypervisor or modifications). This Hypervisor manages all server resources (CPU, memory, and I/O).
Offers excellent isolation, affordable multisource hw and mix OS versions.
Examples of this VM types are : Oracle V, Microsoft Hyper-V, Vmware ESX and Citrix XenServer
Oracle VM Architecture
Built by several components

- Oracle VM agent
- dom0, domU
- Hypervisor
- Server Pools
- Repositories
Oracle VM Functional Architecture
Oracle VM Agent
On x86-based servers the dom0 runs a process called the Oracle VM agent. This agent receives and processes management requests and provides event notification and configuration data to the Oracle VM Manager.
dom0
dom0 it's a privileged domain which is loaded after the hypervisor at boot time. Is responsible for access and security management on the physical server. When dom0 is running you can create VM'S. It's build by several components like a thin kernel based on OEL,open/native linux device drivers. OVM agent, device emulation code to support non pv guests (e.g Windows)
domU
It's an unprivileged/user domain, that is a guest VM on the server. Run any normal server workload.

One domU is not aware of another (isolation).
Hypervisor
Is responsible for allocating resources to domains
Server Pool
Multiple VM servers (from 1 to n), are grouped into a Server pool. Each VM server can be a member of only one server pool. The server pool is the operational unit of Oracle VM
Policies are enforced at the pool level
Repositories
A repository is created to store virtual resources (config files for VM'S, virtual disks, templates and assemblies and ISO files for VM installation). The repositories are presented to be used for the server pools
Oracle VM Manager Architecture
Built by several components

- Oracle VM Manager Database
- Oracle VM Manager UI
- Oracle VM CLI
- Oracle VM Web Server API
- Oracle VM Manager Core
Oracle VM Manager Database
The Oracle VM Manager stores management information in a MySQL local database. This is reserved for Oracle VM Manager Operations.
Oracle VM cli
We can manage the Oracle VM environment using the CLI, either from Oracle VM Manager host or from a remote location. Both methods use SSH protocol
Oracle VM Web Server API
Provides the programming interface to access to Oracle VM objects (virtual machines. virtual disks, etc)
Oracle VM Manager Core
Is often referred as the Oracle VM manager application
Oracle VM Manager HW requirements
Oracle VM Manager SW requirements
Oracle VM Manager is supported on the following operating systems:

Oracle Linux 5 Update 5 64-bit or later.
Oracle Linux 6 64-bit or later.
Oracle Linux 7 64-bit or later.
Red Hat Enterprise Linux 5 Update 5 64-bit or later.
Red Hat Enterprise Linux 6 64-bit or later.
Red Hat Enterprise Linux 7 64-bit or later.
Oracle VM Server HW requirements
Oracle VM Server SW requirements
There are no prerequisite software requirements. Oracle VM Server includes a small Linux-based management operating system
Virtualization Modes
We can find 3 types:

- Hardware virtualized (HVM)
- Paravirtualized (PVM)
- Hardware virtualized with paravirtualized drivers (PVHVM)
Hardware virtualized (HVM)
An unmodified guest operating system executes in complete isolation. Instructions are trapped and emulated at the hardware level (Intel® VT-x/VT-i and AMD-V™). This means that a guest can run without specific modifications to allow for virtualization.
HVM-Supported Linux Guest Operating Systems
CPU Paravirtualized Supported Guest Operating Systems
Paravirtualized (PVM)
A software interface similar but not identical to the underlying hardware is presented to the guest operating system. Paravirtualization provides hooks for guest instructions so that hardware related tasks such as access to network resources, blocks and underlying files can be handled by the management domain instead of the virtual machine, often significantly improving performance, particularly for 32-bit environments. Paravirtualization requires that the guest kernel has support for and loads the PVM drivers to be made aware of the virtual environment.
PV Driver Architecture
For PV guests, driver abstraction

- Replace HW specific drivers
- One network driver
- One block driver
- Very stable/rarely changes
- Excellent guest stability
- Front-end drivers (net and block)
- Inside the VM/domU OS
- Back-end drivers
- In dom0/shared
- Open, native hardware vendor drivers
- Uses open Linux drivers

Each VM is running their one net and block front drivers and they communicate with the dom0, through the net and block back driver
Hardware virtualized with paravirtualized drivers (PVHVM)
Similar to HVM but with additional paravirtualized drivers that are capable of handling I/O related processes directly within the management domain to increase VM performance. This provides the advantages of paravirtualization to an otherwise hardware virtualized guest. This domain type is typically used to run Microsoft Windows™ guests with a limited performance penalty
PVHVM-Supported Linux Guest Operating Systems
HVM and PVHVM-Supported Solaris Guest Operating Systems
Microsoft Windows Supported Guest Operating Systems
Certified Software on Oracle VM
- Oracle Database Single Instance
- Oracle Real Application Clusters (RAC)
- Oracle Fusion Middleware
- Oracle Enterprise Manager
- Oracle Enterprise Performance Management Products (formerly Hyperion)
- JD Edwards
- Berkeley DB
- Times Ten DB
- Oracle E-Business Suite
- Siebel
- PeopleSoft
- Oracle Retail
- Oracle Secure Backup
- Oracle Financial Services Software Limited (formerly iflex Solutions Limited)

Oracle doc id : 464754.1
Hard partitioning with Oracle VM Server for x86
With Oracle VM server for x86, guests are allowed to be pinned or bound to specific physical cores in a single Oracle VM server. Once hard partitioned, the VM guest application only needs to be licensed for the number of physical cores it is pinned to

http://www.oracle.com/technetwork/server-storage/vm/ovm-hardpart-168217.pdf

Oracle doc id : 464754.1
Performance factors on Oracle VM
- Memory management
- Timer managament
- I/O managament
Performance factors - Memory management
Performance factors - Timer management
Performance factors - I/O managament
VM creation methods
- Importing existing virtual machines (oracle vm machines or 3rd party->V2V , virtual to virtual conversion.
- Converting / importing physical machine images (P2V conversion)
- Creating virtual machines from Oracle Templates
- Creation from install media (CD's)
- Pxeboot
Virtual to Virtual conversion (V2V)
- Migrates existing VMware (VMDK) images to Oracle VM images. Oracle VM manager automatically converts a VMware image to Oracle VM format, when importing it.
Physical to Virtual conversion (P2V)
- Offline conversion of any physical machine to Oracle VM HW virtualized guest (HVM)
Supports Linux and Windows. Imports converted image using Oracle VM Manager.
Oracle VM Templates
- Pre-configured VM's containing Oracle (or other products), that are ready to use.
- Contain 1 to N VM's to support composite apps
- Bundled gold images of a preinstalled full stack product (e.g Oracle DB, Primavera, E-Business Suite, etc)
Storage Suported for HA (High Availability)
- NFS
- SAN
- iSCSi
File Systems used in Oracle VM
- NFS
- OCFS2 (Oracle Cluster filesystem)
Filesystem supported for server pool
- Any type of supported shared filesystems (OCFS2 and NFS), but not local filesystem.
Shared Filesystem performance
In terms of performance, NFS is slower for virtual disk I/O compared to a logical volume or a raw disk. This
is due mostly to its file-based nature. For better disk performance you should consider using block-based
storage, which is supported in Oracle VM in the form of iSCSI or Fibre Channel SANs.
Generic Storage connection plugins
The Oracle VM Storage Connect framework provides a storage discovery and provisioning API that enables the provisioning and management of storage platforms directly from within Oracle VM Manager.

Storage elements are logically divided in File Servers and SAN Servers. This distinction refers to the difference between file-based storage and block-based storage, or raw disks

Generic Plugins

- Oracle Generic NFS Plug-in.
- Oracle Generic SCSI Plug-in.
What are Uniform and Non-uniform Exports?
If all servers within a deployment have the same access to file systems exposed by the filer, Oracle VM Manager understands these exports to be uniform. In some cases, an NFS file server may be configured to export mount points with various access restrictions. In the case where some Oracle VM Servers in a deployment are not able to access exports that are available to others, Oracle VM Manager understands these exports to be non-uniform.
What are Access Groups?
Access groups provide a means to arrange and restrict access to storage to a limited set of servers. In Oracle VM there are two types of access groups that ultimately provide very similar functionality:

• File System Access Groups define which Oracle VM Servers have access to a particular file server export or file system. This is commonly used in environments where a file server has non-uniform exports, since it is important to be able to determine which Oracle VM Servers are able to refresh the file system.

• SAN Access Groups define which storage initiators can be used to access physical disks exposed using some form of SAN storage, such as iSCSI or Fibre Channel. SAN access group functionality is defined by the Oracle VM Storage Connect plug-in that you are using. The generic iSCSI plug-in creates a single access group to which all available storage initiators are added at the time of discovery. Other
plug-ins provide more granular control allowing you to create multiple access groups that limit access to particular physical disks according to your requirements
What are Repositories?
A storage repository is essentially logical disk space made available through a file system on top of physical storage hardware. If the storage repository is created on a file server, for example an NFS share, then a file system is already present; if the repository is created on a LUN, an OCFS2 file system is first created.

A storage repository is used to store virtual machine resources, so that these resources can be made available to Oracle VM Servers in a server pool, without having to copy the resources to each Oracle VM Server. The Oracle VM Servers in a server pool gain access to these virtual machine resources by having the storage repository presented to them
Repositories and high availability
Only a server pool with multiple servers, active clustering and attached storage (NFS, iSCSI, fibre channel) can offer high availability, load balancing and similar advanced functionality.
Repositories Structure
It's build by several components

- Assemblies
- ISOS
- Templates
- VirtualDisks
- VirtualMachines files
Assemblies
Contains files for virtual appliances, including OVA packages and unpacked OVF and VMDK files.
ISO
Contains ISO files that can be mounted as virtual CD/DVD drives on virtual machines
Templates
Oracle VM templates are self-contained and pre-configured virtual machines with key Oracle technologies. Each Oracle VM template is packaged using Oracle best practices, which reduces installation and configuration costs, reduces risk and dramatically shortens deployment time lines.
Virtual Disk
Virtual machines need at least one disk from which to boot and run the operating system. Virtual disks
can be part of a template or virtual appliance. Virtual disks can be created when you create the virtual machine or created independently inside the storage repository. Virtual disks can be shared across virtual machines, or dedicated to one virtual machine
VirtualMachines files
Contains virtual machine configuration files , this are the home location of all the virtual machines that have been created in the selected storage repository. You cannot perform any actions on the virtual machine configuration files. If you want to rename, move or delete any of these files, you should perform those operations on the virtual machine, not just the virtual machine configuration
file.
Virtual Machine Resources in a Repository
- Virtual appliances
- Virtual machine templates
- ISO files
- Virtual disks
- Virtual machine files
Virtual appliances
A package that contains one or more preconfigured virtual machines and includes the virtual disks and inter-connectivity between the virtual machines.
Virtual machine templates
A package that contains a virtual machine configuration file and at least one bootable virtual disk. Virtual machine templates are reusable and allow you to to create multiple virtual machines.
ISO files
DVD/CD image files used to create virtual machines from scratch using the installation media.
Virtual Disks
Virtual disks used by virtual machines to perform boot operations, to run the operating system, and to extend the storage capability of virtual machines.
Virtual Machine Disks
Can be assigned to the VM either as virtual disks or physical disks (lun)
Virtual machine files
Configuration files of your virtual machines
Differences between VM Templates and Applliance
The primary distinction between a virtual appliance and a virtual machine template is the file format. Virtual appliances use the .ova format and, in some cases, the .ovf format. Templates use the .tgz format. Virtual appliances can contain multiple virtual machines in a single package while templates contain only a single virtual machine. If you browse the package contents, you can see that an .ova file contains one or more OVF descriptor files and virtual disks whereas a .tgz file contains a virtual machine configuration (vm.cfg) files and one or more virtual disks.
Oracle VM Network Terminology
- Port
- Bond
- Bridge
- VLAN
- VLAN Segment
- VLAN interface
- Logical Network
- Network Channel
Port
The network interface on a server. This term is used interchangeably with NIC (Network Interface
Card). Network ports can be used to host multiple VLAN interfaces. Multiple network ports can be
bonded together for redundancy and performance reasons.
Bond
An aggregation of network ports that act as a single network interface for redundancy and performance reasons. Network bonding is also called Data Link Aggregation. Once a port is part of a bond, it can no longer be used outside of the bond. Oracle VM supports a number of different bonding modes or types. A bond can host multiple VLAN interfaces, or be used as an alternative to a physically cabled port.
Bridge
A method of conjoining different networks together to act as a single network. This technology is only used when creating Virtual Machine networks, and configuration is handled automatically within Oracle VM. Using bridges, virtual machines on one Oracle VM Server are able to communicate with virtual machines on another Oracle VM Server across a network that has been configured for this purpose
VLAN
A method used to virtualize networking at the switch or router for better control over network
separation. VLANs are virtual networks that use identifiers to separate traffic into different networks within the switch. Using VLANs can often reduce network maintenance overhead, as network segregation can be achieved virtually, often from a remote location. Using VLANs can allow servers with a minimal number of physical ports to act as if they were using multiple ports cabled into different networks. Since VLANs can be attached to network bonds, it is possible to achieve the same level of bandwidth that could be achieved using physical cabling by bonding ports together. Although Oracle VM Server can use VLANs, the actual VLAN creation occurs on the switch or router. Network administrators create VLANs and assign VLANs to switch ports on Ethernet switches. The physical cabling from the switch to an Oracle VM Server defines which VLANs are available on the ports or bonds on the Oracle VM Server.
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