Specifies how to load the configuration data, particularly when the candidate configuration and loaded configuration contain conflicting statements. The following are acceptable values:

• merge—Combines the data in the loaded configuration with the candidate configuration. If statements in the loaded configuration conflict with statements in the candidate configuration, the loaded statements replace the candidate ones. This is the default behavior if the action attribute is omitted.
• override—Discards the entire candidate configuration and replaces it with the loaded configuration. When the configuration is later committed, all system processes parse the new configuration.
• replace—Substitutes each hierarchy level or configuration object defined in the loaded configuration for the corresponding level or object in the candidate configuration.

  If providing the configuration data as formatted ASCII text (either in the file named by the url attribute or enclosed in a <configuration-text> tag element), also place the replace: statement on the line directly preceding the statements that represent the hierarchy level or object to replace. For more information, see the discussion of loading a file of configuration data in the CLI User Guide.

  If providing the configuration data as Junos XML tag elements, also set the replace attribute to the value replace on the opening tag of the container tag element that represents the hierarchy level or object to replace.

• set—Loads a set of Junos OS configuration mode commands. This option executes the configuration instructions line by line as they are stored in a file named by the url attribute or enclosed in a <configuration-set> tag element. The instructions can contain any configuration mode command, such as set, delete, edit, or deactivate. When providing the configuration data as a set of commands, the only acceptable value for the format attribute is text. If the action attribute value is set, and the format attribute is omitted, the format automatically defaults to text rather than xml. This option was added in Junos OS Release 11.4.
• update—Compares the loaded configuration and candidate configuration. For each hierarchy level or configuration object that is different in the two configurations, the version in the loaded configuration replaces the version in the candidate configuration. When the configuration is later committed, only system processes that are affected by the changed configuration elements parse the new configuration.

Specifies the format used for the configuration data. There are two acceptable values:

• text—Indicates that configuration data is formatted as ASCII text or as a set of configuration mode commands.

  ASCII text format uses the newline character, tabs and other white space, braces, and square brackets to indicate the hierarchical relationships between the statements. This is the format used in configuration files stored on a routing platform running Junos OS and is displayed by the CLI show configuration command. Set command format consists of a series of Junos OS configuration mode commands and is displayed by the CLI show configuration | display set command. To import a set of configuration mode commands, you must set the action attribute to set.

• xml—Indicates that configuration statements are represented by the corresponding Junos XML tag elements. If the format attribute is omitted, xml is the default format for all values of the action attribute except set, which defaults to format text.

Specifies that the rescue configuration replace the current candidate configuration. The only valid value is rescue.

Specifies the numerical index of the previous configuration to load. Valid values are 0 (zero, for the most recently committed configuration) through one less than the number of stored previous configurations (maximum is 49).