Frequently Asked Questions
- What, exactly is a KVM Switch?
- So what's the point then?
- Do I really need one?
- Isn't this a touch insecure?
Won't anybody be able to access my servers?
- OK, I'm convinced, but will it work
with NT/*nix/BSD .....
- I'll need to be able to link some
servers over 50 metres away. I suppose I'll need a separate switch
for those?
- What's meant by passive / active
switches?
- What is OSD?
- Can I connect my MAC using a KVM
switch ?
- Can I connect my Sun Workstation
using a KVM switch?
- Do KVM switches support USB peripherals?
- Can my switch be located anywhere,
or does it have to be close to the keyboard/mouse?
- Will it cause problems if my servers
are running different screen resolutions?
- When I change servers using my passive
switch, my mouse get's disable after switching. Is it faulty?
- I'm getting ghosted images on my
27" Super WonderMonitor using my HyperImageSuperGFXCard II Ultra.
General
KVM Answers
Q001: What, exactly is a KVM Switch?
A: A KVM switch is a Keyboard, Video, Mouse
switch which enables you to control two or more computer boxes using a
single keyboard, monitor and mouse.
Q002: So what's the point then?
A: An administrater of most modern networks will have to access
multiple servers, maybe an office fileserver, internal web server &
proxy and possibly a separate mail server. A KVM switch will allow
the administrator to use any of these from a single set of components
in a single area making administration more efficient (as well as much
less cluttered!)
Q003: Do I really need one?
A: If you administer more than one server, yes.
Q004: Isn't this a touch insecure?
Won't anybody be able to access my servers? A:
It depends on the switch. Obviously passive switches offer no protection
at all. The Adder range above the AV series offers a programmeable password
which can be used to lock the switch. The high-end Rose Electronics
and Switchcom switches use separate access rights for each user. All
this should largely be irrelevant as your servers won't be
left logged in as the superuser... generally, ...will they?
Q005: OK, I'm convinced but will
it work under NT/*nix/BSD....
A: The majority of switches work invisibly to the host software,
allowing them to be used in completely mixed environments.
Q006: I'll need to be able to link some servers
over 50 metres away. I suppose I'll need a separate switch for
those?
A: No you won't. By attaching a KVM
Extender you can run servers up to 200 metres over cat 5 or 1,000
metres over fibre.
Q007: What's meant by passive / active switches?
A: A passive switch has no active components and is simply hard
wired internally between I/O ports. Computers
are selected manually using a rotary knob on the face of the
switch, It all sounds simple and cheap however passive switches are
not really suitable for today's computer applications.
Active
switches on the other hand incorporate technology to retain the state
of the mice and keyboards connected to them during the switching process
and have circuitry to boost the video signal to avoid ghosting. Many
active switches are powered by the connected computers through the keyboard
cable, whilst others have separate power supplies. Apart from a couple
of manual rotary switches hidden away in the deep recesses of this
site, all the switches we supply are Active from the cheapest
2 port switch up.
Q008: What is OSD?
A: OSD stands for On Screen Display and is a function
which allows you to switch servers using a 'pop-up' menu generated by
the switch. Some switches allow the unique naming of servers for
those who have dozens (or even hundreds) to administer.
Q009: Can I connect my MAC using a KVM switch?
A: Yes. If your MAC has a USB port this can be done inexpensively
for example using the Aten
Petite or Rose
UKBL-2PU both allow for USB computers
although require you to use a PS2 type keyboard. If you need to use your
MAC (USB) keyboard, the
2 port Rextron KAG12 or 4
Port Rextron KAG14 are both reasonably
priced options. There are more expensive multi platform models available
but it is probably best to check with us to be sure they are either necessary
or desirable.
Q010: Can I connect my Sun Workstation using a
KVM switch?
A: Yes. It is possible to connect a Sun using any of the
Multi Platform switches from Fujitsu or Rose Electronics.
Q011:
Do KVM switches support USB peripherals?
A: Whilst the majority of KVM switches do not support
the use of USB keyboards and mice, Some, for example the
2 port Rextron KAG12 or 4
Port Rextron KAG14 both provide a cost effective solution.
Q012: Can my switch be located
anywhere, or does it have to be close to the keyboard/mouse?
A: In normal use (whatever that may mean), the switch is designed
to be situated close to the keyboard, monitor and mouse to allow for the
lack of transmit distance from the keyboard. It can, however be
situated at any point between the KMM and the CPU's by using a KVM
Extender between the KMM and the switch.
Q013: Will it cause problems if
my servers are running different screen resolutions?
A: No.
General Troubleshooting
Q901: When I change servers using
my passive switch, my mouse no longer works after switching. Is
it faulty?
A: This is a well known problem with certain operating
systems and passive switches. It is not a fault of the switch, more
the fault within the drivers of the mouse which are unable to detect when
a PS2 mouse has been plugged in after the OS has gone through its initialisation
upon booting. (It is also known Linux doesn't suffer from this problem)
Q902: I'm getting ghosted/blurred images on my 27"
Super WonderMonitor using my HyperImageSuperGFXCard II Ultra.
A: When running high resolutions / refresh rates over KVM switches
it is considered essential to use the higher-grade coaxial cables for
the monitor connections, even on short runs. You probably have a
standard cable kit. The problem my be remedied by a simple cable
change, however you should check the specification of your switch to ensure
that it is capable of providing the video bandwidth you are demanding
from it.
|
