KB.15.15

Solution:

Identify root cause. Possible reasons for a member not joining an existing stack are:

• The switch being added has already been a member of another stack and has a different

stack ID.

• The maximum number of switches is already configured.

• The switch being added has been statically provisioned, but switch type and MAC address

in the configuration do not match the switch being added.

• There is a problem with the stack cable.

• There is a problem with the stack physical cabling. (illegal topology).

Problem:

The entire stack does not come up after a boot.

Solution:

There are several reasons why all members do not join the stack:

• There is a problem with the stack cable.

• Physical cabling was changed.

• Stack booted on incorrect configuration.

• One or more of the switches has a hardware problem (for example, bad power supply, back

stacking module, corrupt flash).

Problem:

One or more of the members keeps rebooting and does not join the stack.

Possible reasons:

• An unresponsive member.

• Heartbeat loss—a stack that has a member no longer in the stack or a member failing after

joining the stack.

• Illegal topology.

Problem:

After initial boot sequence, the activity and Link LEDs of an interface are not on and the ports are

not passing traffic.

Solutions:

• Identify the “inactive fragment” and provide alternatives for recovery.

• Verify that all OOBMs are connected so that there is uninterrupted access.

Problem:

After a reboot, the selected Command or Standby are not the expected switches.

Solutions:

Check to see if the log files provide a reason why the Commander and Standby were chosen and

which rule they matched.

Troubleshooting stacking 305