Allied Telesis AT-SBx81CFC960 - Manual (Page 311)

SwitchBlade x8106 Chassis Switch and AT-SBx81CFC960 Card Installation Guide
Section III: Building a Stack with VCStack Plus 311
enabled the feature on the switches. If a switch does not have the
license, perform “Activating the VCStack Plus Feature License” on
page 287 to install it. If the command shows that the license is
activated but the feature is not enabled, perform “Enabling the
Stacking Feature” on page 289.
 Use the SHOW LICENSE BRIEF command to confirm that they
have the same feature licenses. If they have different licenses, add
or delete licenses so that they have the same feature licenses.
 Use the SHOW STACK command to compare the ID numbers of
the switches. One switch should have the ID 1 and the other ID 2.
To configure the ID numbers, perform “Setting the ID Number” on
page 293.
You might also try watching for error messages on the Console port on
one of the controller cards when you power on or reset the switches. Here
are the messages:
 The following error message indicates that the two chassis have
different feature licenses. Switches cannot form a stack if they
have different licenses. Perform “Displaying the Feature Licenses”
on page 291 on both switches to determine which switch needs a
license. For example, if, after performing the procedure, you
determine that one of the switches has the premium license and
the other one does not, obtain and install the premium license on
the other unit.
chassis[nnnn] Software feature licensing incompatible. Card
n.n will boot as a standalone system
 This error message indicates that the stack detects one or more
standard SFP+ transceivers in the SFP+ slots of the controller
cards. The SFP+ slots only support stacking transceivers when the
stacking feature is enabled on the switch. Remove the standard
transceivers and replace with stacking transceivers.
EXFX[nnn]: ERROR: stack port n.n.n - Only AT-StackOP support
in this port. Please remove
 This error message indicates that the two switches cannot form the
stack because they have different versions of the AlliedWare Plus
management software. To resolve the problem, update the
software on one of both systems so that they have the same
version.
chassis[nnn]: Neighbor on link portn.n.n cannot join stack -
incompatible stack S/W versions.