Allied Telesis AT-8100 Series - Manual (Page 404)

Chapter 21: Hardware Stacking
404
 You have to assign the switches unique stack ID numbers, in the
range of 1 to 8, with the STACK command in the Global
Configuration mode. You have to assign the numbers before
connecting the switches together with the S1 and S2 ports. (A
stack in which two or more switches have the same ID number will
not function properly.)
 The stack ID number 0 is reserved for stand-alone switches.
 The switch with the lowest ID number is the master switch of the
stack.
 The master switch can be any switch in the stack.
 If the master unit fails or is removed from the stack, the member
switch with the next lowest ID number takes over as the new
master switch.
 The stacking feature described in this chapter is unrelated to the
enhanced stacking feature described in Chapter 23, “Enhanced
Stacking” on page 413. They are completely different features. (At
the time this manual was originally written, 8100S stacking did not
support enhanced stacking. You have to install the switches as
stand-alone units to use enhanced stacking.)
 The 8100L Series switches do not support stacking, but they have
a stack ID LED and an ID number because they use the same
management software as the 8100S Series switches. The correct
ID number of an 8100L Series switch is “0.”
Here are the general guidelines for adding a new switch to an existing
stack:
 You have to assign the new switch an ID number before you add it
to the stack. The range is 1 to 8.
 The ID number for the new switch must be different from the ID
numbers of the existing switches in the stack.
 The ID number for the new switch should be greater than the ID
numbers of the existing switches. For example, if the existing
switches are number 1 to 4, you should assign the new switch the
ID number 5.
 Do not assign the new switch the ID number 0. That number is
reserved for stand-alone operation.
 Power off the new switch before connecting it to the stack. You can
add a switch while it is on, as long as it has a higher ID than the
last member or a lower ID than the current master.
 Removing a stack member will not interrupt the connectivity.
However, adding a stack will interrupt the connectivity, but it will
recover once the stack is formed.