# timing source

#### Syntax

timing source selector { internal | line lineType | uidType interfaceSpecifier }

#### Release Information

Command introduced before JunosE Release 7.1.0.

#### Description

Configures the router’s timing sources. Only one of these timing sources can be an external source received through an interface on an I/O module other than the SRP I/O module; the other two must be either internal sources or external sources received through the SRP I/O modules. There is no no version.

#### Options

- selector—Priority of the timing source; in descending order: primary, secondary, or tertiary
- internal—Specifies the internal SC oscillator
- line—Specifies external timing input on the SRP module
- lineType—One of the following timing sources:
  - e1:a—E1 clock, port A on SRP module
  - e1:b—E1 clock, port B on SRP module
  - t1:a—T1 clock, port A on SRP module
  - t1:b—T1 clock, port B on SRP module
- uidType—One of the following interfaces:
  - ds1—Specifies a DS1 interface
  - ds3—Specifies a DS3 interface
  - e1—Specifies an E1 interface
  - e3—Specifies an E3 interface
  - sonet—Specifies a SONET interface
- interfaceSpecifier—Particular interface; in the form slot/port[:subPort ]

#### Mode

Global Configuration