IT professionals spending any significant time in server rooms
know the importance of good quality keyboard/video/mouse switches.
Plagued with a poor performing KVM switch, even mundane tasks — such as
cleanly rebooting systems, confirming successful backup operations,
downloading and installing OS updates, and completing general
troubleshooting routines — become needlessly complicated.
Whenever you buy a new KVM switch, you want to make sure it meets
your requirements. Review this list to avoid common errors many rookies
or budget-minded organizations suffer when selecting a unit too quickly
or without performing the necessary homework.
1: Proper operation
Little in IT is as frustrating as not being able to properly view a
critical system or connect using a standard keyboard or mouse,
especially as the issue seems to arise at the most crucial times (an
email server is down, the Internet has failed, hundreds of users are
affected, etc.). When you’re combating a stressful failure or outage,
that’s no time to have to fumble around with a flaky KVM.
Perform some due diligence. Whenever you think you’ve found the perfect
KVM, search Internet forums and read Amazon, Newegg, and other reviews
to learn what others’ experiences have been using the same model. If
feedback is positive, you’re good to go. But if proper operation in the
real world proves troublesome, keep searching.
2: Compatibility
KVMs often work with most operating systems, but occasionally glitches
arise. Review a model’s specifications to make sure it’s compatible with
the operating systems it must support. If you don’t, you’ll have to box
everything back up, request an RMA, and send it back.
3: Required connections
I’ve seen seasoned engineers purchase new KVMs that support only DVI
video connections or only PS/2 peripherals, then discover the servers
all have USB- or VGA-only connections. In other cases, engineers assume
that the model they’re buying provides KVM over IP support, when it
doesn’t.
Don’t order a KVM switch haphazardly. Confirm that models support the
connections in place, which may require a quick-and-dirty audit of
current equipment prior to ordering, especially when equipment from
multiple locations is being combined in a single site for the first
time.
4: Port expansion
Shortsighted administrators often purchase eight-port KVM switches when
they need to support eight servers. Whenever possible, purchase KVM
switches with additional capacity. Unforeseen but reasonable decisions
to add a VOIP system, new database platform, HVAC- or alarm-controlling
servers, and other devices instantly place you at a deficit. Too often,
organizations end up with more systems than ports; if possible, purchase
KVM switches with 20% to 25% extra ports.
5: Onscreen display
Onscreen displays (OSD) and menus are kind of like rear-window
defrosters — you don’t miss them until you don’t have them. They provide
visual indications of which systems are online or connected, making it
easier to configure settings and switch between systems. If you’re
accustomed to working with GUI assistance, select a model that supports
OSD. Also consider OSD-enabled KVM switches if you have to switch
frequently between numerous systems, as OSD will make you more
efficient.
6: Mount options
Desktop KVMs work well within many organizations, but they don’t work
well when migrated to server racks. In businesses experiencing growth
but working without a current server room or even half-rack, look for
KVM switches that can be converted to rack mount, should the need arise.
Or start with a standard rack mount unit. Select desktop models only if
you’re confident the unit will never end up servicing systems mounted
in a professional rack or cabinet.
7: Electrical power
KVM switches with their own power supply work more consistently, in my
experience, than do those that draw their electrical supply from the
systems they connect to. Even many budget-priced KVM switches include
optional power supply connections but don’t ship with a standalone power
adapter. Always check to see whether a power adapter is included with,
or supported by, the unit you select. If no power supply is included,
visit a nearby Radio Shack or electronics store to purchase the missing
component, after assuring its compatibility.
8: Sufficient cable length
More than once, I’ve seen six-foot KVM cables prove too short when wound
through cable management infrastructure. As part of a pre-purchase
audit, measure the distances the KVM’s cables must cover. Ensure that
included cables, or those you purchase separately, are long enough to
span the required distances. It sounds academic, but KVM cables are
expensive, even when purchased in bulk, and they are painful to have to
rerun in server cabinets after discovering the just-purchased items are
too short.
9: Reset button
Occasionally, KVM memory becomes corrupted. Since KVMs frequently
receive power not only from a standalone power adapter but also from the
systems the KVM switch is connected to, it can prove difficult to clear
a corrupted KVM switch’s electronics. No one should have to climb
behind a server rack to physically disconnect four, eight, or even 16
systems just to clear a frozen
KVM. Look for systems that have a simple
reset button.
10: Audio support
While less common, some environments require that system audio be
available from the systems the
KVM Controls. Of course, not all KVM
switches support audio. Review a specific model’s individual
specifications to confirm that it will support audio. Otherwise, you
could find yourself stuck with convoluted workarounds resulting in a
cacophony of noise. Prevent headaches. KVM switches can be very
unforgiving. P
erform your homework up front.
By
Rahisystems.com
