Owner's Manual

Managing a Switch Stack 145
Connecting switches in a ring topology allows the stack to utilize the
redundant communication path to each switch. If a switch in a ring topology
fails, the stack can automatically establish a new communications path to the
other switches. Switches not stacked in a ring topology may split into multiple
independent stacks upon the failure of a single switch or stacking link.
Additional stacking connections can be made between adjacent switch units
to increase the stacking bandwidth, provided that all redundant stacking links
have the same bandwidth. It is strongly recommended that the stacking
bandwidth be kept equal across of all stacking connections; that is, avoid
mixing single and double stacking connections within a stack. Up to eight
redundant stacking links can be configured on a stacking unit (four in each
direction).
Creating a PowerConnect M6220 Stack
You can stack up to 12 PowerConnect M6220 units, supporting up to 240
1-Gb ports. PCM6220 switches can be stacked only with other PCM6220
switches. Create a stack by connecting adjacent units using the stacking ports
on the top of the switch panel.
1
Install a separately purchased stacking module in Bay 1 of each of the
switches in the stack.
2 For each switch in the stack, connect one of the short stacking cables from
stacking port one on the switch to stacking port two on the next switch.
3 If necessary, use a separately purchased, long (3 meter) stacking cable to
connect the switches. Repeat this process until all of the devices are
connected.
4 Use the remaining stacking cable to connect the remaining free ports, from
port one of the last switch to port two of the first switch.