Allied Telesis AT-SBx81CFC960, Installation Manual

Page: 305 / 324

SwitchBlade x8112 Chassis Switch and AT-SBx81CFC960 Card Installation Guide
Section III: Building a Stack with VCStack Plus 305
Powering On the Stack
The two switches are now ready to operate as a stack. But before
powering on the stack for the first time, you may find it useful to review the
information in “Controlling the Selection of the Initial Active Master
Controller Card” on page 305. The information is important if one of the
switches was a stand-alone unit in your network and you want it to retain
its configuration when it becomes part of the stack.
Note
If you did not power off the chassis earlier in these instructions, you
must reset both units with the REBOOT command in the Privileged
Exec mode. After resetting the units, go to “Monitoring the Boot Up
Sequence” on page 306 or “Verifying the Stack” on page 309.
Controlling the
Selection of the
Initial Active
Master
Controller Card
The manner in which you initially power on the units can determine which
controller card becomes the active master controller card for the stack.
This, in turn, can determine the initial configuration of the stack. In some
situations you may want to control which controller card becomes the initial
active master card.
There are two ways to power on the switches of the stack, either
simultaneously or one after the other:
 If you power on the units simultaneously, the controller cards use
their priority values or MAC addresses to determine the active
master card for the stack. The selected active card uses the
settings in its configuration file as the initial configuration for the
stack. For background information, refer to “Priority Numbers” on
page 283.
 If you power on one switch, wait a minimum of ten seconds, and
then power on the second unit, the active master controller card in
the unit first powered on becomes the master controller card for the
stack. Its configuration file becomes the initial configuration for the
stack.
The selection of the active master card might not be important to you if the
units and controller cards of the stack are new. Here, the stack uses the
default settings regardless of which controller card becomes the active
card. If this is the case, you can power on the units either way,
However, if one of the switches was a stand-alone unit in your network and
you are adding a new chassis to build a stack, you might want to retain the
stand-alone configuration on the first switch to avoid having to reconfigure
it when it becomes part of the stack. You can do this by powering it on first
so that its active master controller card becomes the active card for the