You may not be thinking of scalability when you design a room to house your servers and other network components, but your job will be made much easier when the network starts to grow if you've taken that growth into account at the beginning. 

In a small business, "the" (one and only) server may sit in a corner of someone's office or hide out in a small storage closet. There are problems with those solutions: they aren’t very secure, and they aren’t very scalable. If office space is at a premium, it might be difficult to convince management that your servers need their own room (and good luck on getting the boss to sacrifice the only wasted space on the premises--part of his big corner office--to construct one).

But if the organization is serious about protecting its IT investments, it’s important to find a way to build a proper server room, one that offers physical security for the machines that host your most mission-critical applications and store your important data. But how do you make a small space scalable? Let’s look at some ways to do just that.

Selecting the space

If you have the option, select a space that’s larger than you currently need to accommodate future growth. Your business may be operating with a single server solution like Microsoft Small Business Server (SBS) now, but as the company grows, you’ll almost certainly find your network evolving beyond its limitations.

For security, performance and useability reasons, you will probably eventually want to separate your domain controller from other server functions, install the perimeter firewall on its own separate server, and perhaps create a DMZ or perimeter network where you’ll place mail and web servers and others that need to have direct contact with the Internet. When your company implements wireless, you’ll need a place for one or more WAPs. When it decides to cut the telco cord and go with Voice over IP, you’ll need room for a call server/IP PBX. All these new devices will necessitate more switches and routers.  And the heat they generate may dictate the need for a good cooling system.

You may be thinking that if the company grows large enough to need individual servers and all these extra goodies, you’ll have so many employees that you’ll have to move to different quarters anyway. That may or may not prove true. Many organizations today are saving money by allowing employees to work from home, implementing second shifts, and finding other ways to accommodate an increase in the number of employees without requiring more office space. However, the increased network traffic and productivity resulting from remote users and/or 'round the clock use of the network’s resources will increase the load on the IT infrastructure and will likely require restructuring and/or additional devices in the server room.

Populating the space

As you set up or add to the infrastructure, keep scalability in mind. For instance, if you add a second server, you might purchase a KVM so both servers can share a keyboard, monitor and pointing device. Instead of buying a two-port KVM to meet your immediate needs, it may make more sense in terms of scalability to look at one that will let you add additional servers as they’re needed.

Don’t forget the concept of physical scalability when you choose a form factor for those new servers, either. Especially in a limited space, a rack-mount or blade system is far more scalable than tower style servers. You can put a dozen rack-mounted servers in the same amount of space that would be used by only a couple of tower machines. The extra cost for the rack-mount form factor might be offset by the savings in space, especially in tight real estate markets where square footage is at a premium.

On the other hand, keep in mind that rack-mount servers are themselves limited in expansion capabilities. There’s little or no room to mount extra internal drives or to add expansion cards for additional functionality (for example, you might need to add additional network interface cards for multi-homed servers). These limits on expandability should be balanced against the space savings in accordance with your individual current and future needs.

Increasing scalability with virtualization technology

Another way to increase the physical scalability of your servers is to buy powerful machines and run several logical servers on one physical server with virtualization software. This can also save you money, since you’ll need to buy fewer machines.

You can use VMWare’s free VMWare Server or Microsoft’s Virtual Server 2005 to install multiple instances of your server operating systems, and then install the appropriate server applications on each. Thus you could have three logical servers, seen by the network as three different computers with their own individual IP addresses, running on a single machine.

Expanding the space

No matter how efficiently you pack the room, eventually you’ll probably need more space than it offers. That’s why it’s a good idea to consider, in the beginning, how and where you might be able to expand in the future. A server room that backs up to another room that you might later be able to commandeer could save you a lot of grief years from now. Which would you prefer to deal with: cutting a door into the office on the other side of the server room wall to double your floor space, or having to move everything (not to mention all that rewiring) in order to move into a room twice the size on the other side of the building?

Remember that as the organization grows, you’ll need that extra space for such things as a testbed network where you can check out new operating systems and applications or make sure service packs and updates are compatibility with your applications before deploying them on the production network, or distribution servers for more control over patch management.

Summary

Scalability is important in relation to more than just your network hardware and software; it’s also an important consideration when designing the space in which your network components live.