Bayside Networks National Provider of Trusted and Experienced IT Services

BaysideNetworks best practices code: SVR - server hardware issues and OBL - Obsolescence Planning

Administrator: “Server ABC is old, we need to upgrade it. The age of the hardware is a concern and it’s very low on disk space. The system has crashed several times recently because of low disk space.� (Already sounds familiar, right?)

Manager: “Ok – let’s replace it. That’s what we have to do, right? The manager thinks to himself: We will buy a newer server because that’s what we always do when this happens.�

Three years later the cycle repeats.

If you are like many offices, you seem to be buying new servers faster than you get rid of the old servers. Over time, many offices end up with far more server boxes than they really need. Many of these older systems are still running “something” that keeps you from getting rid of them. All of this leads to system functionality being spread too thin and across too many different systems of widely different types and ages.

Frustrating, costly and never ending server upgrades and migrations.

There is a way to deal with this paradigm – it’s called server virtualization.

In short, virtualization allows a single piece of server hardware to run multiple file server operating systems and their respective services within each operating system. Depending on what the servers are doing, a fast server with plenty of memory can easily run up to 30 server operating systems within it. Basically you can run many server systems on a single strong server hardware system.

Any server that typically runs with low to medium long term CPU utilization is a great candidate for virtualization. Web servers, domain controllers, storage servers, network services boxes, such as DHCP servers are all great candidates.

Boxes that run with very high CPU utilization such as busy SQL servers and large Exchange servers are not great candidates for virtualization as boxes like this really need all the CPU cycles they can get to maximize speed.

Chances are good that if your office has more than 5 servers, at least 3 out of 5 of your server boxes are good candidates for virtualization.

Virtualization is not a new idea. It is a long standing practice with mainframe operating systems, going back 25 or more years. Virtualization is usually referred to as “logical partitioning� in the mainframe context. Old school mainframe guys often talk about how many “LPARS� (logical partitions) a specific mainframe could reliably run – it was a good indication of how powerful a machine was. Virtualization is now a reliable option for Intel based server platforms, making the benefits available to smaller businesses and server systems.

What can virtualization do for you?

• Large potential cost savings if you are paying for rack space in a co-located environment. Take 10 server boxes and consolidate them into one box — do the math.
• Power savings — Not a minor issue if you look at the monthly cost for running 10 separate server boxes instead of 1 larger server box. Power costs can easily exceed the cost of server hardware over the life of a server system.
• Less server hardware to buy.
• Software licensing savings: Some manufacturers, such as Microsoft, allow a single licensed copy of their “Advanced Server” product to be loaded on up to 5 virtual servers within the same server box. One copy of Advanced Server is far less expensive than 5 copies of “Standard Server.”
• Easy to move servers from one box to another: Virtualized servers can be moved from one virtual server to another, usually within seconds. If you need to take a virtual server down for service you can migrate the servers it contains to other virtual servers very quickly, usually without any noticeable network disruption. Basically every virtual server is “just a file” that can be transferred and used on any other virtual server system with adequate resources to run it.It’s a crude analogy but think of moving the “hibernation fileâ€? from a notebook computer along with a ghost image of its hard drive to another system – basically moving the personality of a system from one system to another. This is similar to how server images can be moved from one virtual server to another.
• Virtualized servers share their disk space — every virtualized server is a self contained SAN; where all the servers on that virtual box share the available disk space. No more frustrating situations where one box has tons of disk space and another has no space.
• Buy one big fault tolerant Virtual server box and thereby make all the server processes that it runs fault tolerant. This helps system reliability and is much better than running lots of different boxes of varying age strata many of which are likely to have suspect or limited fault tolerant provisions.
• Much more limited need for KVM switches and all the related cabling and equipment. Ten traditional servers need ten computers worth of KVM support. One virtual server that contains ten virtual boxes needs just one KVM.

Guidelines for virtualization

• The two major virtualization products are VMWARE (we prefer the ESX version) and Microsoft’s Virtual Server product.
  1. VMWARE: www.vmware.com/
  2. Microsoft Virtual Server: www.microsoft.com/windowsserversystem/virtualserver
• If you are interested in virtualization, be sure to confirm that your server hardware is compatible with the virtualization software that you plan to run. For example, VMWARE ESX requires that your system run SCSI drives and it only works with certain motherboards and LAN adaptors.
• Major manufacturers, like Dell, are selling server machines that are certified to run VMWare. It is a very good idea to use hardware that is certified for the virtualization software system that you plan to use. There is detailed hardware compatibility information available from VMWare and Microsoft on their respective products.
• To scale your Virtual server box, make a list of the separate traditional server boxes that you would need to accommodate your system’s needs. Work through the scaling exercise available on the VMWare site to design a server platform that is large enough to virtualize your servers.
• Don’t plan on virtualizing everything. Be sure to leave at least one domain controller out of the virtual system and it’s also best to not virtualize very busy Exchange and or SQL type servers.
• Microsoft and VMWare offer fully functional free (time bombed) trial-ware versions of their basic virtualization products. VMWare actually released a free version of their GSX Virtual server software that is very good — many people use it to run several operating systems on their PC’s. It’s a great way to load up and run Linux and Windows on the same machine at the same time.
• It’s worth noting the Virtualization software works with just about any operating system. Most common operating systems, such as Windows, Linux and Novell based systems run fine within a virtual environment.