Black Box SW722A-R4 Switch User Manual


 
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SERVSWITCH™
3.3 Cascading in ServSwitch Systems
In a normal cascaded ServSwitch system, the shared monitor(s), keyboard(s), and
mouse (mice) are directly attached to one or more “master” Serv-Switches, while all
the CPUs are indirectly attached through “submasters” (subsidiary ServSwitches,
ServSwitch Ultras, ServManagers, etc.) that provide port expansion but may or may
not perform any control functions of their own. When you cascade in this way, you
can expand your system to include up to 256 ports (sixteen 16-port submasters on
a 16-port master unit).
CAUTION!
To avoid platform- and peripheral-mismatch problems, take these
precautions:
1. In any application involving CPUs belonging to different platforms,
we recommend that you use multiplatform Serv type switches
(ServSwitch Ultras, ServManagers, etc.) as masters and submasters.
2. If you attach any PC-only submasters to a multiplatform master,
make sure you attach only IBM PC compatible CPUs to those
submasters.
3. If you use any PC-only masters, we recommend that you use only
PC-only submasters. If you must use any ServManager or ServSwitch
Ultra submasters, make sure that you have those submasters set for the
keyboard and mouse type you’re using with [Ctrl] Mxx [Enter], and make
sure that those settings are saved in the submasters’ NVRAM with
[Ctrl] K.
4. All of the CPUs attached to any PC-only submaster must use the
same type of keyboard and mouse.
You can add submasters to your ServSwitch system as you need them. For each
submaster you add to the system, you add as many ports as are on that submaster,
minus the one port on each master “above” it that’s now occupied. Refer to
Figure 3-2 on the next page:
Connecting one 4-port submaster Serv unit to a 4-port master ServSwitch (top
view) gives you a total of 7 ports: 4 on the submaster and another 3 (4 minus
the one that the submaster is attached to) on the master.
Connecting four 4-port submaster Serv units to a 4-port master ServSwitch
(bottom view) gives you a total of 16 ports, 4 on each submaster. (All 4 ports
on the master are now occupied.)
When you use Matrix ServSwitches as submasters, the setup is a little more compli-
cated. Refer to Figure 3-3 on page 29: Connecting two 4-port Matrix ServSwitch
submasters to an 8-port ServSwitch master gives you a total of 14 ports on that
master. (Each of the masters in Figure 3-3 can access 14 ports, but while both
masters share CPUs 1 through 8, CPUs 9 through 14 on either master can only be
accessed by the monitors, keyboards, and mice on that master. Note that when we