clocking

Syntax

clocking (external | internal);

Hierarchy Level

[edit interfaces interface-name]

Description

Clock source for the interface. You specify this statement for interfaces that can use various clock sources.

For DS-3 channels on a Channelized OC-12 interface, DS-1 channels on a Channelized DS-3 interface, and DS-0 channels on a Channelized E1 interface, the clocking statement is supported only for channel 0; it is ignored if included in the configuration of channels 1 through 11. The clock source configured for channel 0 applies to all channels on the Channelized OC-12, Channelized DS-3, and Channelized E1 interfaces. The individual DS-3, DS-1, and DS-0 channels use a gapped 45-MHz clock as the transmit clock.

On Channelized STM-1 interfaces, you should configure the clock source at one side of the connection to be internal (the default JUNOS configuration) and configure the other side of the connection to be external.

Options

external—The clock source is provided by the DCE.

internal—Use the internal stratum 3 clock as the reference clock.

Default: internal

Usage Guidelines

See Configure the Clock Source or page "Configure the Clock Source" and Clock Sources on Channelized Interfaces.

Required Privilege Level

interface—To view this statement in the configuration.
interface-control—To add this statement to the configuration.