Stack Master - NETGEAR M4200 Software Administration Manual

Stack Master

The stack master is the single point of stack-wide management. From the stack master, you
can configure:
• System-level (global) features that apply to all stack members
• Interface-level features for all interfaces on any stack member
A switch stack is identified in the network by its network IP address. The network IP address
is assigned according to the MAC address of the stack master. Every stack member is
uniquely identified by its own stack member number.
The stack master contains the saved and running configuration files for the switch stack. The
configuration files include the system-level settings for the switch stack and the
interface-level settings for all stack members. Each stack member retains a copy of the
saved file for backup purposes. If the master is removed from the stack, another member is
elected master, and then runs from that saved configuration.
All stack members are eligible stack masters. If the stack master becomes unavailable, the
remaining stack members participate in electing a new stack master. A set of factors
determine which switch is elected the stack master. The stack master is elected or re-elected
based on one of these factors and in the order listed:
1. The switch that is currently the stack master
2. The switch with the highest stack member priority value
Note: NETGEAR recommends assigning the highest priority value to the
switch that you prefer to be the stack master. This ensures that the
switch is re-elected as stack master if a re-election occurs.
3. The switch with the higher MAC address
A stack master retains its role unless one of these events occurs:
• The stack master is removed from the switch stack.
• The stack master is reset or powered off.
• The stack master fails.
• The switch stack membership is increased by adding powered-on standalone switches or
switch stacks.
In the case of a master re-election, the new stack master becomes available after a few
seconds. In the meantime, the switch stack uses the forwarding tables in memory to
minimize network disruption. The physical interfaces on the other available stack members
are not affected while a new stack master is elected. If a new stack master is elected and the
previous stack master becomes available, the previous stack master does not resume its role
as stack master.
Managed Switches
Switch Stacks
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