Allied Telesis AlliedWare Plus Operating System Version 5.4.4C (x310-26FT,x310-26FP,x310-50FT,x310-50FP) - Manual (Page 2121)

VCStack Introduction
Software Reference for x310 Series Switches
C613-50046-01 REV A AlliedWare Plus TM Operating System - Version 5.4.4C 82.7
Stack Formation
As previously mentioned, a VCStack always contains a stack (active) master plus a number
of stack (backup) members. To be part of a stack, a switch must connect to other potential
stack members via dedicated stacking ports. See
Figure 82-7 .
Figure 82-7: Stacking Ports
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 VCStack.
The Role of the Stack Master
In addition to being a member of its VCStack, 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 on page 83.21 . 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 on page 83.11 .
The master is the switch with the lowest priority setting, or if the priority settings are
equal, 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.
x310 Stacking-Ports.eps
CLASS 1 LASER PRODUCT
CONSOLE
S1/51
S2/52
49 SFP+
50
x510-52GTX
3 5 1 7 9
4 6 8 10 2
Stacking
Ports