Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

 
ON THIS PAGE
 

CLI Configuration Mode Overview

The configuration mode of the Junos OS CLI enables you to configure a device, using configuration statements to set, manage, and monitor device properties.

Understanding CLI Configuration Mode

You can configure all Junos OS properties, including interfaces, general routing information, routing protocols, and user access, as well as several system hardware properties.

As Understanding the Junos OS CLI Modes, Commands, and Statement Hierarchies describes, a device configuration is stored as a hierarchy of statements. In configuration mode, you create a set of configuration statements to use. When you finish entering the configuration statements and are certain they are complete and correct, you commit them, which activates the configuration on the device.

You can create the configuration interactively, or you can create an ASCII text file containing the configuration, load it on the device, and commit it.

Configuration Mode Commands

The following table summarizes each CLI configuration mode command. The commands are organized alphabetically.

Table 1: Summary of Configuration Mode Commands

Command

Description

activate

Remove the inactive: tag from a statement. Statements or identifiers that have been activated take effect when you next issue the commit command.

annotate

Add comments to a configuration. You can add comments only at the current hierarchy level.

commit

Commit the set of changes to the database and cause the changes to take operational effect.

copy

Make a copy of an existing statement in the configuration.

deactivate

Add the inactive: tag to a statement, effectively commenting out the statement or identifier from the configuration. Statements or identifiers marked as inactive are ignored when you issue the commit command.

delete

Delete a statement or identifier. All subordinate statements and identifiers contained within the specified statement path are deleted with it.

edit

Move inside the specified statement hierarchy. If the statement does not exist, it is created.

exit

Exit the current level of the statement hierarchy, returning to the level before the last edit command, or exit from configuration mode. The quit and exit commands are equivalent.

extension

Manage configurations that SDK application packages contribute. Manage them by either displaying or deleting user-defined configurations that the named SDK application package contributed. A configuration defined in any native Junos OS package is never deleted by the extension command.

help

Display help about available configuration statements.

insert

Insert an identifier into an existing hierarchy.

load

Load a configuration from an ASCII configuration file or from terminal input. Your current location in the configuration hierarchy is ignored when the load operation occurs.

quit

Exit the current level of the statement hierarchy, returning to the level before the last edit command, or exit from configuration mode. The quit and exit commands are equivalent.

rename

Rename an existing configuration statement or identifier.

replace

Replace identifiers or values in a configuration.

rollback

Return to a previously committed configuration. The software saves the last 10 committed configurations, including the rollback number, date, time, and name of the user who issued the commit configuration command.

run

Run a CLI command without exiting from configuration mode.

save

Save the configuration to an ASCII file. The configuration statements up to and including the current level of the statement hierarchy are saved, along with the statement hierarchy containing it. This action allows a section of the configuration to be saved, while fully specifying the statement hierarchy.

set

Create a statement hierarchy and set identifier values. This command is similar to edit, except that your current level in the hierarchy does not change.

show

Display the current configuration.

status

Display the users currently editing the configuration.

top

Return to the top level of configuration command mode, which is indicated by the [edit] banner.

up

Move up one level in the statement hierarchy.

update

Update a private database.

wildcard delete

Delete a statement or identifier. All subordinate statements and identifiers contained within the specified statement path are deleted with it. You can use regular expressions to specify a pattern. Based on this pattern, the operating system searches for items that contain these patterns and deletes them.

Configuration Statements and Identifiers

You can configure device properties by including the corresponding statements in the configuration. Typically, a statement consists of a system-defined keyword, which is fixed text, and an optional identifier. An identifier is an identifying name that you can define, such as the name of an interface or a username, which enables you and the CLI to differentiate among a collection of statements.

Table 2 lists top-level configuration statements. See CLI Explorer for information about each configuration statement.

Table 2: Configuration Mode Top-Level Statements

Statement

Description

access

Configure the Challenge Handshake Authentication Protocol (CHAP).

accounting-options

Configure accounting statistics data collection for interfaces and firewall filters.

chassis

Configure properties of the router chassis, including conditions that activate alarms and SONET/SDH framing and concatenation properties.

class-of-service

Configure class-of-service parameters.

firewall

Configure filters that select packets based on their contents.

forwarding-options

Configure forwarding options, including traffic sampling options.

groups

Configure configuration groups.

interfaces

Configure interface information, such as encapsulation, interfaces, virtual channel identifiers (VCIs), and data-link connection identifiers (DLCIs).

policy-options

Configure routing policies, which enable you to filter and set properties in incoming and outgoing routes.

protocols

Configure routing protocols, including BGP, IS-IS, LDP, MPLS, OSPF, RIP, and RSVP.

routing-instances

Configure one or more routing instances.

routing-options

Configure protocol-independent routing options, such as static routes, autonomous system numbers, confederation members, and global tracing (debugging) operations to log.

security

Configure IP Security (IPsec) services.

snmp

Configure SNMP community strings, interfaces, traps, and notifications.

system

Configure systemwide properties, including the hostname, domain name, Domain Name System (DNS) server, user logins and permissions, mappings between hostnames and addresses, and software processes.

Configuration Statement Hierarchy

The Junos OS configuration consists of a hierarchy of statements. There are two types of statements:

  • Container statements, which are branches that can contain other statements (including additional container statements or leaf statements). Container statements at the top of the hierarchy are considered to be the trunk of the hierarchy tree.

  • Leaf statements (contained by container statements), which do not contain other statements.

The container and leaf statements form the configuration hierarchy. Each statement at the top level of the configuration hierarchy resides at the trunk of a hierarchy tree. These top-level statements are container statements, containing other statements that form the tree branches. The leaf statements are the leaves of the hierarchy tree. An individual hierarchy of statements, which starts at the trunk of the hierarchy tree, is called a statement path.

The following illustration shows the hierarchy tree, illustrating a statement path for the part of the protocol configuration hierarchy responsible for configuring the hello-interval statement on an interface in an OSPF area.

Figure 1: Configuration Mode Hierarchy of Statements Configuration Mode Hierarchy of Statements

The protocols statement is a top-level statement at the trunk of the configuration tree. The ospf, area, and interface statements are all subordinate container statements of a higher statement (they are branches of the hierarchy tree). The hello-interval statement is a leaf on the tree, which in this case contains a data value, namely the length of the hello-interval, in seconds.

The following configuration example illustrates the statement hierarchy as shown in Figure 1:

[edit protocols ospf area area-number interface interface-name]

The command displays the configuration as follows:

The CLI indents each level in the hierarchy to indicate each statement’s relative position in the hierarchy. Additionally, in general, it sets off each level with braces, using an open brace at the beginning of each hierarchy level and a closing brace at the end. If the statement at a hierarchy level is empty, the braces are not printed.

Each leaf statement ends with a semicolon. If the hierarchy does not extend as far as a leaf statement, the last statement in the hierarchy ends with a semicolon.

The configuration hierarchy can also contain “oneliners” at the lowest level in the hierarchy. Oneliners remove one level of braces in the syntax and display the container statement, its identifiers, the child or leaf statement, and its attributes all on one line.

For example, dynamic-profile dynamic-profile-name aggregate-clients; is a oneliner because the dynamic-profile statement, its identifier dynamic-profile-name, and leaf statement aggregate-clients all appear on one line when you run the show command in configuration mode:

Enter and Exit CLI Configuration Mode

You configure Junos OS by entering configuration mode and creating a hierarchy of configuration mode statements.

  • To enter configuration mode, use the configure command.

    When you enter configuration mode, the following configuration mode commands are available:

    Note:

    When making configuration changes, commit them before you exit. If you exit configuration mode without committing configuration changes, you lose the intended changes.

    You must have configure permission to view and use the configure command. When in configuration mode, you can view and modify only those statements for which you have access privileges.

  • If you enter configuration mode and another user is also in configuration mode, a message shows the user’s name and the part of the configuration the other user is viewing or editing:

    Up to 32 users can be in configuration mode simultaneously, and they all can make changes to the configuration at the same time.

  • To exit configuration mode, use the exit configuration-mode configuration mode command from any level, or use the exit command from the top level. For example:

    If you try to exit fconfiguration mode using the exit command and the configuration contains changes that you have not committed, you see the following message and prompt:

  • To exit with uncommitted changes without having to respond to a prompt, use the exit configuration-mode command. This command is useful when you are using scripts to perform remote configuration.

See Also

Relative Configuration Mode Commands

The top or up command followed by another configuration command—such as edit, insert, delete, deactivate, annotate, or show—enables you to quickly move to the top of the hierarchy or to a level above the area you are configuring.

To issue configuration mode commands from the top of the hierarchy, use the top command and specify a configuration command. For example:

To issue configuration mode commands from a location higher up in the hierarchy, use the up configuration mode command. Specify the number of levels you want to move up in the hierarchy, and then specify a configuration command. For example:

See Also

Command Completion in Configuration Mode

This topic shows you how to access command help and to use basic command completion in CLI configuration mode. In each case, you access help by using the question mark (?) character, either alone or with a partial command or configuration statement.

To list the configuration mode commands, use the ? command alone:

To list all the statements available at a particular hierarchy level, use ? after the name of the hierarchy level you wish to view. In this example, see the edit and edit protocols hierarchies:

To list all commands that start with a particular string or letter, enter the string, letter, or both, and then enter the ? character. This example shows all the routing-options commands starting with the letter “a”:

This example shows all configured xe- interfaces. You can display these interfaces by using the first two letters of the abbreviation (ex) and the ? character:

You can also show a list of all configured policy statements:

See Also

Notational Conventions Used in Configuration Hierarchies

When you are working in CLI configuration mode, the banner on the line preceding the prompt indicates the current hierarchy level. In the following example, the level is [edit protocols ospf]:

Note:

Junos OS documentation uses user@host# as the standard configuration mode prompt. In a CLI session, the prompt shows your user ID and the configured name of the Juniper Networks device you are working on.

Use the set ? command to display the statements that you can include in the configuration at the current level. The help apropos command is also context-sensitive, displaying matching statements only at the current command hierarchy level and below.

Statements are listed alphabetically within each hierarchy and subhierarchy. An exception occurs if a subhierarchy is so long that it might be difficult to determine where it ends and its next peer statement begins. In case of a very long subhierarchy, the subhierarchy appears at the end of its parent hierarchy instead of in alphabetical order. In this exception scenario, a placeholder appears in the alphabetical position where the subhierarchy would have been listed.

For example, at the [edit interfaces interface-name unit logical-unit-number] hierarchy level, the family family-name subhierarchy has more than 20 child statements, including several subhierarchies with child statements of their own. The full family family-name hierarchy appears at the end of its parent hierarchy ([edit interfaces interface-name unit logical-unit-number]), and the following placeholder appears at its alphabetical position:

Another exception to alphabetical order is that the disable statement always appears first in any hierarchy that includes it.