17
How cascade connections operate
The method for cascading ServSwitch CX units is straightforward
and requires no hardware settings or lengthy configuration process.
This is due to the
Port Direct
communication system that allows
them to locate each other and share information.
The method of linking ServSwitch CX units is the same regardless
of the cascade level, or number of devices attached. Put simply:
•
A single cascade link is made by connecting a
COMPUTER
CONNECTIONS
socket of one unit to a
CATx USER PORTS
socket of the unit below it.
Such a single link would allow just one user from the higher
ServSwitch CX unit to access any of the server systems attached
to the lower one. However, a single link can cause a bottleneck
for multi-user systems so you are strongly recommended to use a
minimum of two or three links. Ideally quad links should be used
wherever possible as these allow four users to simultaneously
access computer systems situated anywhere within the cascade
tree.
When cascade links are made between units, each ServSwitch CX
will automatically recognise the links and treat them accordingly.
The connections within dual, triple or quad cascade links will
then be allocated to users according to their general availability
in that group, not as specific individual lines. The diagram here
summarises the groups into which the ports are arranged
When connecting links, ensure that you use the lowest numbered
ports in each group. For example, to create a triple cascade link
in group A, use ports 1, 2 and 3; for a double cascade link in
group B, use ports 5 and 6, etc. Unused ports in a group can be
utilised to connect directly to normal computers. The Port Direct
system will automatically distinguish between the different types of
connections.
The central purpose of the link group system is that each user can
use a unique address to locate a particular computer. However, as
with the Internet, the route to get there could be slightly different
each time. This avoids any route blocking that could easily be
caused by other users occupying any specific link lines.
Note: Single, dual, triple and quad link groups may be mixed
on one unit providing the differing link groups lie within the
appropriate group boundaries shown opposite - see
Tips for
successful cascading
for more details.
Port groups for cascade links
(sixteen port models use groups A to D only)
See also
•
Addressing servers in a cascade
•
Connecting ServSwitch CX units in cascade
•
Testing specific links to cascaded servers
