Cisco Catalyst 2960 Series, Configuration Manual

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configuration using the copy running-config destination-url command, storing the replacement file either
locally or remotely. However, this method lacked any automated file management. On the other hand, the
Configuration Replace and Configuration Rollback feature provides the capability to automatically save copies
of the running configuration to the Cisco IOS configuration archive. These archived files serve as checkpoint
configuration references and can be used by the
configure replace command to revert to previous configuration
states.
The
archive config
command allows you to save Cisco IOS configurations in the configuration archive using
a standard location and filename prefix that is automatically appended with an incremental version number
(and optional timestamp) as each consecutive file is saved. This functionality provides a means for consistent
identification of saved Cisco IOS configuration files. You can specify how many versions of the running
configuration are kept in the archive. After the maximum number of files are saved in the archive, the oldest
file is automatically deleted when the next, most recent file is saved. The
show archive command displays
information for all configuration files saved in the Cisco IOS configuration archive.
The Cisco IOS configuration archive, in which the configuration files are stored and available for use with
the
configure replace command, can be located on the following file systems: FTP, HTTP, RCP, TFTP.
Configuration Replace
The configure replace privileged EXEC command replaces the running configuration with any saved
configuration file. When you enter the configure replace command, the running configuration is compared
with the specified replacement configuration, and a set of configuration differences is generated. The resulting
differences are used to replace the configuration. The configuration replacement operation is usually completed
in no more than three passes. To prevent looping behavior no more than five passes are performed.
You can use the copy source-url running-config privileged EXEC command to copy a stored configuration
file to the running configuration. When using this command as an alternative to the configure replace target-ur l
privileged EXEC command, note these major differences:
• The
copy
source-url
running-config
command is a merge operation and preserves all the commands
from both the source file and the running configuration. This command does not remove commands
from the running configuration that are not present in the source file. In contrast, the
configure
replace target-url command removes commands from the running configuration that are not present in
the replacement file and adds commands to the running configuration that are not present.
• You can use a partial configuration file as the source file for the
copy
source-url
running-config
command.
You must use a complete configuration file as the replacement file for the configure replace target-url
command.
Configuration Rollback
You can also use the configure replace command to roll back changes that were made since the previous
configuration was saved. Instead of basing the rollback operation on a specific set of changes that were applied,
the configuration rollback capability reverts to a specific configuration based on a saved configuration file.
If you want the configuration rollback capability, you must first save the running configuration before making
any configuration changes. Then, after entering configuration changes, you can use that saved configuration
file to roll back the changes by using the
configure replace target-url command.
You can specify any saved configuration file as the rollback configuration. You are not limited to a fixed
number of rollbacks, as is the case in some rollback models.
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
2060
Replacing and Rolling Back Configurations