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Cisco Catalyst Blade Switch 3120 for HP Software Configuration Guide
OL-12247-01
Chapter 5 Managing Switch Stacks
Understanding Switch Stacks
Note
Auto-advise and auto-copy identify which images are running by examining the info file and by
searching the directory structure on the switch stack. If you download your image by using the copy tftp:
boot loader command instead of the archive download-sw privileged EXEC command, the proper
directory structure is not created. For more information about the info file, see the
“File Format of
Images on a Server or Cisco.com” section on page B-25
.
Incompatible Software and Stack Member Image Upgrades
You can upgrade a switch that has an incompatible universal software image by using the archive
copy-sw privileged EXEC command. It copies the software image from an existing stack member to the
one with incompatible software. That switch automatically reloads and joins the stack as a fully
functioning member. For more information, see the
“Copying an Image File from One Stack Member to
Another” section on page B-39
.
Switch Stack Configuration Files
The configuration files record these settings:
•
System-level (global) configuration settings—such as IP, STP, VLAN, and SNMP settings—that
apply to all stack members
•
Stack member interface-specific configuration settings that are specific for each stack member
The stack master has the saved and running configuration files for the switch stack. All stack members
periodically receive synchronized copies of the configuration files from the stack master. If the stack
master becomes unavailable, any stack member assuming the role of stack master has the latest
configuration files.
Note
We recommend that all stack members run Cisco IOS Release 12.2(40)EX or later. The interface-specific
settings of the stack master are saved if the stack master is replaced without saving the running
configuration to the startup configuration.
When a new, out-of-box switch joins a switch stack, it uses the system-level settings of that switch stack.
If a switch is moved to a different switch stack, that switch loses its saved configuration file and uses the
system-level configuration of the new switch stack.
The interface-specific configuration of each stack member is associated with the stack member number.
As mentioned in the
“Stack Member Numbers” section on page 5-8
, stack members retain their numbers
unless they are manually changed or they are already used by another member in the same switch stack.
•
If an interface-specific configuration does not exist for that member number, the stack member uses
its default interface-specific configuration.
•
If an interface-specific configuration exists for that member number, the stack member uses the
interface-specific configuration associated with that member number.
If a stack member fails and you replace with it with an identical model, the replacement switch
automatically uses the same interface-specific configuration as the failed switch. Hence, you do not need
to reconfigure the interface settings. The replacement switch must have the same stack member number
as the failed switch. For information about the benefits of provisioning a switch stack, see the
“Switch
Stack Offline Configuration” section on page 5-9
.