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CHAPTER 7: Operation
7.3.3 T
HE
I
NACTIVITY
T
IMEOUT
(D
UAL
-A
CCESS
S
YSTEMS
O
NLY
)
Because two user stations (one local, one remote) can be attached for each CPU,
Dual-Access Rackmount Extender systems have “shared access” features, including
Private Mode (see
Section 7.3.4
) and an “inactivity timeout.” While the inactivity
timeout isn’t controlled by a keyboard command per se, it responds to general
keyboard activity.
The two stations attached to the Extender normally contend for access. When
there has been no keyboard or mouse activity on one station for the duration of
the “inactivity timeout” period, the Extender will switch to the first station from
which it detects user activity. With the Micro Remotes and the Switching Remote
Unit, both keyboard keypresses and mouse movements always register as user
activity. The default behavior with the other Remotes is to register only keyboard
keypresses as user activity, but you can set them to register mouse movements as
well if you want to (see
Section 5.3.1
).
(
Important:
Serial and audio communication between the CPU and the remote
devices do
not
affect, and are
not
affected by, KVM contention. They can begin,
continue uninterrupted, and cease regardless of which user is in KVM control,
without causing a change of KVM control or resetting the inactivity timeout.)
The “inactivity timeout” prevents a user at the other station from interrupting
work in progress at the active station. With the Micro Remotes and Switching
Remote Unit, the timeout is fixed at two seconds. This is also the default timeout
length for the other Remotes, but you can set them to fifteen seconds if control is
being switched too quickly (see
Section 5.3.1
).
Here’s how it works: A user station is activated by pressing a key on its keyboard
or by moving the mouse. This first keypress, or the first packet of mouse data, is
absorbed by the Extender and is not passed on to the PC. The Extender “latches
onto” this user station; users at the other station can see what’s happening on their
monitor, but can’t control the PC with their keyboard or mouse while the active
station is in use. Once the active station’s keyboard and mouse are idle for the
length of the “inactivity timeout,” the Extender “lets go” of that station, and will
switch to whichever station it next detects keyboard input from.
When the Switching Remote Unit boots up, it gives any local user station control
of the local CPU and the remote user station control of any attached and powered
remote CPU. But when a Dual-Access Extender system without a Switching Remote
Unit boots up, it gives control (and its total attention) to the local station for at
least a portion of the inactivity-timeout period. This means that the remote
monitor in a Dual-Access system might be blank, and the remote keyboard and
mouse inactive, for up to several seconds.
