User guide

loopback (ADSL, DS0, E1/E3, SONET/SDH, SHDSL, and T1/T3)

Syntax loopback (local | payload | remote);

Hierarchy Level [edit interfaces ce1-fpc/pic/port],

[edit interfaces ct1-fpc/pic/port],

[edit interfaces t1-fpc/pic/port],

[edit interfaces interface-name ds0-options],

[edit interfaces interface-name dsl-options],

[edit interfaces interface-name e1-options],

[edit interfaces interface-name e3-options],

[edit interfaces interface-name shdsl-options},

[edit interfaces interface-name sonet-options],

[edit interfaces interface-name t1-options],

[edit interfaces interface-name t3-options]

Release Information Statement introduced before Junos OS Release 7.4.

Statement introduced in Junos OS Release 12.2 for the ACX Series Universal Access

Routers.

Description Configure a loopback connection. To turn off the loopback capability, remove the loopback

statement from the configuration.

NOTE: When configuring CE1 or CT1 interfaces on 10-port Channelized E1/T1

IQE PICs, the loopback statement must be included with the local or remote

option at the [edit interfaces ce1-fpc/pic/port] or [edit interfaces

ct1-fpc/pic/port] hierarchy level as appropriate.

When configuring T1 interfaces on 10-port Channelized E1/T1 IQE PICs, the

loopback statement must be included with the payload option at the [edit

interfaces t1-fpc/pic/port] hierarchy level.

NOTE: When configuring CE1 or CT1 interfaces on the 16-port Channelized

E1/T1 MIC (MIC-3D-16CHE1-T1-CE), you must include the loopback statement

at the [edit interfaces ce1-fpc/pic/port] hierarchy level, or [edit interfaces

ct1-fpc/pic/port]

To configure loopback on channelized IQ and IQE PICs, SONET/SDH level, use the

sonet-options loopback statement local and remote options at the controller interface

(coc48, cstm16, coc12, cstm4, coc3, cstm1). It is ignored for path-level interfaces

so-fpc/pic/port or so-fpc/pic/port:channel.

Options local—Loop packets, including both data and timing information, back on the local router’s

PIC. NxDS0 IQ interfaces do not support local loopback.

Chapter 4: Statement Summary