FusionAccess Desktop Cloud Service Provisioning

Why use cloning technology?

In the traditional office scene, computers are used by employees in the form of a physical machine. Then the physical installation of the operating system and office software, you need to consume a very large human and material resources.

Therefore, in the current environment, more and more businesses, schools choose to deploy Office / school room of cloud desktop cloud desktop approach. what are the benefits?

1. Operation and maintenance cost management declined
2. Secure the safety information
3. Deployed to enhance the efficiency
4. …………

So we in the process of the desktop cloud deployment, in order to meet the different needs of the various scenarios, such as: read and write high performance requirements of the scene; call center this scenario and so on. Desktop cloud when issued, it can be divided into full copy and linked clones. There are subdivided into fast and full-package memory. Following specific talk about these types of cloning technology.

Full copy

As can be seen from the figure
a complete copy of a virtual machine - to create a separate virtual machine from a template, then these out to create a virtual machine with the source virtual machine (VM templates) are independent of each other, they affect each other. No matter what you do operations on the source virtual machine will not affect a complete copy of a virtual machine.

So we can summarize its advantages and disadvantages
advantages : Each virtual machine paid out is an individual, just like we created multiple virtual machines the same. Users on its own virtual machine can save the personalization file, make some personal changes.
Drawback : each virtual machine will be paid out of the occupied independent resources (including: CPU, memory, disk), a large resource overhead. When carried out the operation and maintenance of these virtual machines, each virtual machine needs to operate (software upgrades, installing applications, etc.)

Here also, by the way, when we make a complete copy of the template, the final step required the template package.

Why packaging ?
Conventional installation system, is performed by the Setup program, so the length of the relatively long time required for installation.
The system is packaged in the form of a complete copy of the packaging system, in the form of paste and then further mounted on a system disk. Therefore, the faster the speed.

Since the packaging system takes time, so in order to reduce the time of issuance of a virtual machine issues a complete copy slow, the introduction of the "Fast Package"

Fast Package

Rapid and complete copy of the package in essence no different.
Its unique point reflected in the "fast", it does not use sysprep package, but was renamed Canadian domain by the virtual machine applications.

This step is not required because the system package, so it issued when the virtual machine is more efficient

Linked clones

A linked clone is the most mainstream of desktop virtualization way

Technical features :
the same operating system virtual machines share the same master image, and the personalization data generated by the virtual machine running in the process is stored in the respective differential which the disc.
Since all of the linked-clone virtual machines are using the same master image, so storage space is significantly reduced, no longer have to install the operating system on each virtual machine, and each virtual machine requires only save their own personality in which the differential disc data can be. Issued speed has been greatly improved, creating a virtual machine speed is very fast.
When maintenance operations on each virtual machine, only need to maintain master data which can be completed maintenance operations for all virtual machines to facilitate the management, operation and maintenance to improve efficiency.

Restrictions :
IO performance requirements for the master is very high, especially in the case of multiple virtual machines simultaneously boot all virtual machines need to read the operating system-related files from the master of them, and therefore the efficiency of the boot will receive influences. (Boot storms)

It is suitable for task-based desktop, such as call center scene.

Link clone volume - principle

be used as shown in FIG linked clone VM clone volume actually linked together by linking clone mapping and clone the parent roll roll combination differential link, provided to the virtual machine. (Note the point: All the linked-clone virtual machine to the parent roll can only be read )

And linked clone difference volume is a writable volume , which disk is streamlined configuration mode, each have a linked clone VM, save for the difference data. (By default, the virtual machine data stored in a disk machine difference will be cleared automatically.)

To summarize Linked Clones value :

1. Create a virtual machine speed in seconds, shortening the time of issuance, improve the efficiency of payment.
2. Save a lot of storage space, reducing business / school IT costs
3. Unified system can update the linked clone virtual machine patching and other operations to facilitate the operation and maintenance management.

Planning for storage of linked clones
can see from two perspectives:

1. Storage capacity dimensions: Total Hard = (Roundup (total number / 128, 0) + size * total number of master disc size difference *) / effective capacity per disk hot spare rate *
2. Storage IOPS dimensions: total number of hard disk = (total number * (+ IOPS differential master disk IOPS)) / * valid IOPS per plate of hot spare

Full memory

We have just mentioned, if more than one VM while turning the power, prone to "IO storm" in the scene linked clones, because at the same time to read the master data among multiple virtual machines at this time, it received a limiting disk IO performance start will be very slow.

Therefore, the whole memory table is created. We all know that our memory compared to hard disk storage, there are more IO read and write performance. Here go online using heavy compression technology, the virtual desktop storage to read and write is converted to read and write memory. Greatly improves IO performance, solve the problem of "IO storm".

Principle :

the use of memory to heavy compression and multiplexing, the system disk desktop virtual machines all into memory, disk read and write operations makes the desktop virtual machine memory into operation, greatly enhance the user experience ...
(Note: Desktop also belong to the whole memory linked-clone desktop)

Advantages :
full memory speed advantage of the desktop with linked-clone desktops, as well as high performance in addition to reading and writing. Start, restart the virtual machine is very fast.
Provide emergency disk protection mechanism, to ensure that once when memory end business without interruption.