Allied Telesis x600-48Ts/XP - Manual (Page 46)

Chapter 2: Virtual Chassis Stacking
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Stack Formation
A virtual chassis stack (VCS) always contains a master plus a number of
stack members. To be part of a stack, a switch must connect to other
potential stack members via dedicated stacking ports on the VCS Stacking
module located in the rear of the switch. Figure 19 shows a stacking AT-
StackXG module. Refer to “AT-StackXG Module Installation” on page 61
to install this module.
Figure 19. VCS Stacking Module
Once the switches have been physically connected to form a stack,
powering all the members on automatically sets off a number of processes
that enable the stack members to detect the presence of the other stack
members and form themselves into a VCS.
The Role of the
Stack Master
In addition to being a member of its VCS stack, the stack master manages
functions such as software version control and distribution, routing
processing, and network management.
Selecting the Stack Master
The stack members are able to automatically select which switch will
become the stack master. This selection is based on two components:
1. The stack member’s priority setting.
2. The stack member’s MAC address.
For both components, the lower the number the higher the priority. To set
the stack priority, run the stack priority command. Note that changes to
these settings will not take effect until the next master re-election. To
display these components run the show stack command.
The master is the switch with the lowest ‘priority setting’, or if no ‘priority
settings’ are configured, the switch with the lowest MAC address will
become the stack master. When a stack member is initially booted, its
priority value defaults to 128. Therefore if all switches retain their defaults,
then the stack master will be determined by MAC address comparison.
AT-StackXG
STACK PORT 1 STACK PORT 2
x600-stackXG Module