Stack Cabling - Alcatel-Lucent OmniSwitch 6850E Series Hardware User's Manual

Managing OmniSwitch 6850E Series Stacks

Stack Cabling

Switches in a stack are connected to each other by stacking cables. The stacking cables come in various
lenghts and types as as listed on
in a stack.
Stacking cables for can be connected in any pattern. In other words, the cable connected to stacking port A
of one switch can be connected to either stacking port A or stacking port B of the adjacent switch.
However, it is strongly recommended that the cabling pattern remains consistent across the stack. In addi-
tion, for a stack to have effective redundancy, a redundant stacking cable must be installed between the
upper-most and bottom-most switch at all times. This provides effective failover in the event of a stacking
link or module failure within the stack.
The diagram below shows two recommended stacking cable patterns. For detailed information on assem-
bling a stack and connecting the cables, refer to
ware Components."
Note. When planning the stack cabling configuration, keep in mind that the switch connected to stacking
port A of the primary switch will be assigned the secondary management role by default.
Examples of Stacking Cable Patterns (Chassis Rear Panels Shown)
OmniSwitch 6850E Series Hardware Users Guide
page 6-3 and provide high-speed, dual-redundant links between switches
Chapter 2, "OmniSwitch 6850 Series Chassis and Hard-
A B
A B
January 2013
A stack of eight switches in a crossed (stacking port
A to stacking port B) configuration. Note that a
redundant stacking cable connection exists between
the top and bottom switches. This connection is
required for effective redundancy across the stack.
A stack of eight switches in a straight (stacking port A
to stacking port A; stacking port B to stacking port B)
configuration. Note that a redundant stacking cable
connection exists between the top and bottom
switches. Again, this connection is required for
effective redundancy across the stack.
Stack Cabling
page 6-17