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Your office has grown. It’s come to the point where you want to monitor what’s happening on the network and install software without effort. Also, there are those inevitable emergencies for which, so far, you don’t have a great plan: such as every time there’s a virus or the e-mail system has crashed, you don’t have speedy backup in place. What you need is a KVM switch.
In the simplest case, a KVM switch enables you to place a keyboard, monitor and mouse in your server room and switch this between servers when you want to configure them, install new software or just monitor what’s going on. Unlike software or remote access technologies, KVM switches work across all hardware and software platforms, with both new and old computers.
But for emergencies, you need more than the minimum. You need speed and reliability, which puts you in the professional league of switches. For businesses, a KVM switch has to work like a pro, no matter what.
A good KVM switch will work faultlessly every time, but this isn’t the case with every switch. If you ask around, chances are you’ll find someone who has horror stories to tell. Typical experiences include switches that hang randomly or mice that go crazy, requiring a reboot of the KVM switch.
Other reports include endlessly repeating key strokes, computers that fail to boot in the required video resolution, lazy mice and keys that get stuck down for no apparent reason. Coping with such issues while you’re trying to get your company’s e-mail back online can be frustrating, to say the least.
So, how do you decide which KVM switch to choose? Choosing and implementing a worthwhile KVM switch means viewing it as key to the infrastructure, like a hub, rather than as a commodity item.
Best Practices Feature Set
Best practices feature set
Even though traditionally a technology for larger server rooms, you want a “CATx” switch. When you really look at the feature set, it’s perfect for a small server room. These switches use a small “dongle” that connects to the computer, and cheap, thin, ubiquitous CATx (for example, CAT5, CAT5e, CAT6, etc.) cable to connect the dongle to the KVM switch. This approach has several advantages.
First, the dongles enable the KVM switch to be connected to any computer by simply choosing the right dongle (for example, PS/2, USB, Sun, etc.). Second, internal “keep alive” circuitry within the dongles means that the KVM switch can be disconnected or repowered without affecting the computers.
Third, the CATx-style cables mean that the KVM switch itself can be physically small, rather than half the size of a bus-always important in small server rooms that quickly become cramped.
Last, but by no means least, the CATx cables are much thinner and easier to manage than more traditional, bulky KVM cables-which are cumbersome to route around and under racks and equipment shelves. If you pile up the number of KVM cables you may need to connect, say, 10 computers, the space that traditional cables occupy can be quite astonishing. With more computers, the problem just gets worse.
In comparison, CATx cables take up relatively little space, and have the advantage of being disconnected at both ends, neatly fed through small holes and routed easily around corners.
A few more pieces of shopping advice: It’s always worth getting a KVM switch with an On-Screen Display (OSD) because you won’t always remember which computer you’ve connected to which port. And if you’re planning to use a USB keyboard, it’s worth checking that your new KVM switch supports USB on the KVM console end. Most CATx-style KVM switches support a choice of connections, so you shouldn’t have a problem.
Also, make sure you get a switch with expansion or cascade ability. The number of servers you have will likely grow, so don’t think that you can just connect one to another. This may be electrically possible, but if it’s not a fully-designed cascade strategy, it will leave you with a whole load of operational confusion.
Potential problems
One potential problem to be aware of is Display Data Channel (DDC) support, which can cause significant frustration. Some switches offer no DDC support; others switch the DDC signals to the monitor when the computer is selected. Others present fixed DDC Extended display identification data (EDID) data. But the most sophisticated will clone the EDID data from the connected monitor.
These distinctions really matter if you want the computer to output the right video mode and you don’t want to have to switch to each computer as they power up. The safest option is to choose a KVM switch that clones its DDC EDID data. One aspect that you won’t often see on a KVM switch vendor’s spec sheets is the switch’s latency characteristic but it’s nevertheless important.
How to Choose the Right KVM Switch for Your Small Server Room
pagebreak title: Deciding on Class and Remote Access Capabilities}
Deciding on class and remote access capabilities
Next, you will need to decide on the class of KVM switch that you need. Matrix switches enable two or more users to work on different computers at the same time, and tend to be specified when the numbers of computers becomes larger.
For many small server room requirements, a single-channel KVM switch may well be sufficient-particularly when you bear in mind that many computers have built-in remote access capabilities too, and that these are typically used alongside a KVM switching function.
But perhaps the most important decision to make is whether or not you want built-in remote access capabilities. There are two remote access technologies that are typically employed on KVM switches: CATx extension technology, which enables you to place a remote access unit up to 1,000 feet away from the KVM switch and connect it via CATx trunk cabling. This technology is relatively cheap and gives a great user experience.
The alternative is a built-in, KVM-over-IP engine that enables you to connect to the KVM switch over your IP network from anywhere in the world. This function is more expensive but tends to be really popular with users because it provides a single point of access to all the computers, is simple to administer, and enables computers to be maintained from anywhere within the organization or around the world.
Setting up is plug and play
It’s pretty much a plug and play experience with a standard KVM switch, although it’s always worth configuring the OSD to show the names of your computers. Setting up a KVM-over-IP engine is also pretty straightforward and, on a good KVM switch, will be driven by the OSD. It’s a relatively simple task of selecting a password, IP address and subnet mask, and then connecting the switch to your network.
Many professional-grade KVM switches will be both desk and rack-mountable, so it’s not normally a problem to mount the switches in the most convenient place. Administration is usually simple, as most switches will enable several user profiles to be set up that give different computer access rights. The beauty of KVM switches is that they require very little training and are generally extremely simple to use.