# t1 clock source

#### Syntax

t1 channel clock source { line | internal { module | chassis } }

no t1 channel clock source

#### Release Information

Command introduced before JunosE Release 7.1.0.

#### Description

Determines which end of the T1 interface provides clocking. The no version uses the default value, line.

#### Options

- channel—One or more individual T1 channels, ranges of T1 channels, or combination of individual channels and ranges, in the range 1–28 (no spaces); for example, 3,7-15,19-13,27
- line—Interface transmits data from a clock recovered from the line’s receive data stream
- internal—Interface transmits data using its internal clock. You must specify one of the following for internal clocking:
  - module—Internal clock is from the line module itself
  - chassis—Internal clock is from the configured system clock

#### Mode

Controller Configuration