Restrictions for Configuration Replace and Configuration
Rollback
If the device does not have free memory larger than the combined size of the two configuration files (the
current running configuration and the saved replacement configuration), the configuration replace operation
is not performed.
Certain Cisco configuration commands such as those pertaining to physical components of a networking
device (for example, physical interfaces) cannot be added or removed from the running configuration. For
example, a configuration replace operation cannot remove the
interface ethernet 0
command line from the
current running configuration if that interface is physically present on the device. Similarly, the
interface
ethernet 1
command line cannot be added to the running configuration if no such interface is physically
present on the device. A configuration replace operation that attempts to perform these types of changes results
in error messages indicating that these specific command lines failed.
In very rare cases, certain Cisco configuration commands cannot be removed from the running configuration
without reloading the device. A configuration replace operation that attempts to remove this type of command
results in error messages indicating that these specific command lines failed.
Information About Configuration Replace and Configuration
Rollback
Configuration Archive
The Cisco IOS configuration archive is intended to provide a mechanism to store, organize, and manage an
archive of Cisco IOS configuration files to enhance the configuration rollback capability provided by the
configure replace
command. Before this feature was introduced, you could save copies of the running
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.
System Management Configuration Guide, Cisco IOS XE Fuji 16.8.x (Catalyst 9500 Switches)
218
Configuration Replace and Configuration Rollback
Restrictions for Configuration Replace and Configuration Rollback
