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5-2
Cisco Catalyst Blade Switch 3120 for HP Software Configuration Guide
OL-12247-01
Chapter 5 Managing Switch Stacks
Understanding Switch Stacks
All stack members are eligible to be stack masters. If the stack master becomes unavailable, the
remaining stack members elect a new stack master from among themselves. The switch with the highest
stack member priority value becomes the new stack master.
The system-level features supported on the stack master are supported on the entire switch stack. If a
switch in the stack is running the IP base or IP services feature set and the cryptographic (that is,
supporting encryption) universal software image, we recommend that this switch be the stack master.
Encryption features are unavailable if the stack master is running the IP base or IP services feature set
and the noncryptographic software image.
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 each stack member. Each stack member has a current copy of these files for back-up purposes.
You manage the switch stack through a single IP address. The IP address is a system-level setting and is
not specific to the stack master or to any other stack member. You can manage the stack through the same
IP address even if you remove the stack master or any other stack member from the stack.
You can use these methods to manage switch stacks:
•
Network Assistant (available on Cisco.com)
•
Command-line interface (CLI) over a serial connection to the console port of any stack member or
the Ethernet management port of a stack member
•
A network management application through the Simple Network Management Protocol (SNMP)
Use SNMP to manage network features across the switch stack that are defined by supported MIBs.
The switch does not support MIBs to manage stacking-specific features such as stack membership
and election.
•
CiscoWorks network management software
To manage switch stacks, you should understand:
•
These concepts on how switch stacks are formed:
–
Switch Stack Membership, page 5-3
–
Stack Master Election and Re-Election, page 5-6
•
These concepts on how switch stacks and stack members are configured:
–
Switch Stack Bridge ID and Router MAC Address, page 5-8
–
Stack Member Numbers, page 5-8
–
Stack Member Priority Values, page 5-9
–
Switch Stack Offline Configuration, page 5-9
–
Hardware Compatibility and SDM Mismatch Mode in Switch Stacks, page 5-11
–
Switch Stack Software Compatibility Recommendations, page 5-11
–
Stack Protocol Version Compatibility, page 5-12
–
Major Version Number Incompatibility Among Switches, page 5-12
–
Minor Version Number Incompatibility Among Switches, page 5-12
–
Incompatible Software and Stack Member Image Upgrades, page 5-16
–
Switch Stack Configuration Files, page 5-16
–
Additional Considerations for System-Wide Configuration on Switch Stacks, page 5-17