Stack Cabling
Managing OmniSwitch 6855 Series Stacks
page 7-18
OmniSwitch 6855 Series Hardware Users Guide
September 2011
Redundant Stacking Cable Connection
OmniSwitches allow redundant stacking cable connections between the top-most and bottom-most
switches in a stack.
Important.
For a stacked configuration to have effective redundancy, a redundant stacking cable must be
installed between the upper-most and bottom-most switch in the chassis at all times.
The figure below shows how the redundant connection between the top and bottom switches in the stack
ensures that data will continue to flow throughout the stack, even in the event of a connection failure at
one of the stacking cables.
Stacking Cable Redundancy: Recovery Following a Stacking Link Failure
Data enters slot 1 via Ethernet port. The data is passed to
slot 2 over the stacking cable connection, then exits slot 2
via one of its Ethernet ports.
1
2
The stacking connection between slots 1 and 2 goes
down unexpectedly. Data can no longer travel directly
between slot 1 and 2.
However, because there is a redundant connection (the
cable between slot 1 and slot 4), data is immediately
passed to slot 4, then quickly traverses slot 3 and exits
slot 2 to its destination.
Slot 1
Slot 2
Slot 3
Slot 4
Chassis Front
Stacking Cables
Slot 1
Slot 2
Slot 3
Slot 4
