No Backup
Stack Member Identification
© Copyright Lenovo 2016
If a Backup is not configured on the active Master, or the specified Backup is not
operating, then if the active Master fails, the stack will reboot without an active
Master.
When a group of stacked switches are rebooted without an active Master present,
the switches are considered to be isolated. All isolated switches in the stack are
placed in a WAITING state until a Master appears. During this WAITING period, all
the ports, except the management port and stacking ports, of these Member
switches are placed into operator‐disabled state. Without the Master, a stack
cannot respond correctly to networking events.
Each switch in the stack has two numeric identifiers, as follows:
Attached Switch Number (asnum)
An asnum is automatically assigned by the Master switch, based on each
Member switch's physical connection in relation to the Master. The asnum is
mainly used as an internal ID by the Master switch and is not user‐configurable.
Configured Switch Number (csnum):
The csnum is the logical switch ID assigned by the stack administrator. The
csnum is used in most stacking‐related configuration commands and switch
information output. It is also used as a port prefix to distinguish the relationship
between the ports on different switches in the stack.
It is recommended that asnum 1 and csnum 1 be used for identifying the Master
switch. By default, csnum 1 is assigned to the Master. If csnum 1 is not available,
the lowest available csnum is assigned to the Master.
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Chapter 18: Stacking