RokNewsPager Virtualization

Virtualization

  • Traditional Server
  • Virtualization
  • Hardware Advantages

1. Traditional Server

A traditional server is a dedicated centralized computer used by other users on the network.  It can have a variety of functions: from a simple file repository, mail server, database server, web server, etc.  It runs a stable server operating system and is usually installed on server grade hardware with built-in redundancies to improve reliability. Even though you can have a server with redundant power supplies, hard drives, and other components; there are still single points of failure, such as the mother board.  So if that server has a hardware fault, all your users are going offline.
It gets worse: What if the RAID controller that runs the redundant hard drive array dies? You may or may not be able to rebuild the drive array. The traditional answer was to add more redundant components to your server; which adds cost.  There’s no such thing as a redundant mother board system, so you still have a single point of failure. You can keep a spare motherboard on hand in case it dies, but you still have server downtime while you troubleshoot and repair it.  The next step up is to create a cluster server; which costs even more money. With this, you can use two servers, now called “nodes”, all with redundant power supplies, hard drives, etc. You can connect those to a Storage Area Network (SAN) device (which is a big array of hard drives); once again with redundant power supplies, hard drives, network cards, and redundant RAID controllers.  To link all this together so that you have a fail-over (called Fault Tolerance), you need to have not just standard server software, but the Enterprise Edition; which costs even more money. But you now have a system that can tolerate a failure of any component on the system without causing the server to be offline.  What if you need more than one server and want the same degree of reliability out of that system too?  The traditional answer was to ante up and purchase another redundant server system. Another aspect of the traditional server system is that if you were to analyze your server performance and utilization in detail, you may be surprised to find that each server may only be utilizing 5-20% of the CPU and memory resources. The remaining 80-95% of system resources are usually idle.

2. What Is Virtualization?

This may be a difficult concept to visualize. Essentially, it is a method of taking a  physical server or workstation, and turning it into a virtual machine that operates inside a larger, managed hardware environment. Virtual machines are not dependent on hardware to the same extent as it was on a physical computer. Each virtual machine still has the appearance and functionality of the original computer in every way just as if it were still on the original hardware. Users on the network will not be able to see any difference.
Once a server has been virtualized, its existence is now equivalent to just a file that can be relocated to almost any piece of hardware.  So if your host machine has a hardware failure, you can simply move your virtual machines to another host and users will not be the wiser; except for the small amount of down time needed to bring the virtual machines up on an alternate host.

3. Hardware Advantages of Virtualization

The advantage to using virtual servers is that you can run multiple virtual machines on one physical server. So let’s say you take that über-server cluster we discussed earlier and use it as your virtual server host system, all the virtual machines running on it will benefit from the ultra-reliability of that impressive hardware array. Downtime can be completely eliminated for hardware failures if fault tolerance is set up properly; which automatically maintains your virtual server operations even if one entire node goes down.

 

Have ITS create a custom virtualization solution for your business. Solutions range from creating simple virtual servers to an entire server and virtual desktop infrastructure.