19
3 Connect the other
end of the cascade
link cable to one of
the
CATx USER PORTS
sockets on the rear
panel of the lower
unit. Due to the way
in which ports within
a link group are
dynamically allocated,
it is not usually
important exactly
which user port is
connected to each
server port of the
upper unit.
4 Repeat steps 2 and 3 for each of the links within the group, adhering to the
Group numbering diagram
for the correct link group boundaries on the
COMPUTER CONNECTIONS
ports of the upper switch.
Once the ServSwitch CX units and servers have been connected, you can edit
their names to make it much easier to locate them. See the
To create/edit
server names
section in the Configuration chapter for more details.
Connecting ServSwitch CX units in cascade
Please consider the following when making cascade connections between
ServSwitch CX units.
Tips for successful cascading
• The maximum number of levels for a cascade is three.
• The maximum number of server systems that can be controlled within a
cascade installation depends upon the ServSwitch CX unit placed at the
top level. If the top level unit is a non-IP version, a maximum of 512 server
systems can be controlled. However, if the top level unit is a ServSwitch CX
with IP, the maximum number of servers drops to 128. This is due to the
extra burden placed on the unit’s memory of administering global (IP) users.
• The number of links between units determines the number of users that can
simultaneously access the computers situated further down the tree. Link
groups of one and two links should be discouraged.
• Ensure that cascade links (within a group) between units are approximately
the same length.
• Triple and quad link groups may be mixed on one unit providing the
links lie within the appropriate port boundaries designated in the
Group
numbering diagram
.
• ServSwitch CX
with IP
models can only be used at the top level of the
cascade tree because they have only two
CATx USER PORTS
sockets.
• For each cascade link, use a standard category 5, 5e or 6 twisted-pair cable,
terminated at each end with an RJ45 connector. There must be no crossover
connections within the cable, i.e. do not use patch cables. The cascade link
cables can be up to 50m (160 feet) in length. However, remember that
the overall length between any remote user (via a ServSwitch CX Remote
extender) and any server (via a SAM) must not exceed 300m (980 feet) - that
figure includes the cascade link cables. Ensure that each of the links within a
cascade group all conform to the same length.
• The procedure given opposite may be carried out in any order but for clarity
the instruction will begin at the higher level ServSwitch CX unit (here called
the
upper unit
), i.e. the one that is being fed into by a unit at the cascade
level below (here called the
lower unit
). The procedure remains the same
regardless of exactly which cascade levels are being connected. The basic
rule is that each link is made by connecting a
COMPUTER CONNECTIONS
port of
the upper switch to a
CATx USER PORTS
of the lower switch.
To connect units in cascade
1 Ensure that power is disconnected from the ServSwitch CX and all other
units to be connected.
2 Connect one end of each
cascade link cable to an
appropriate
COMPUTER
CONNECTIONS
port on the rear
panel of the upper unit. Refer
to the
Group numbering
diagram
for the correct link
group boundaries.
See also
•
Testing specific links to cascaded servers
