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test interface t1-bert-start



Release Information

Command introduced before Junos OS Release 7.4.


Start a bit error rate test (BERT) on a T1 interface.


interface-nameInterface name: t1-fpc/pic/port or ct1-fpc/pic/port <:channel>.

Additional Information

Before starting a BERT, you must disable the interface. To do so, include the disable statement at the [edit interfaces interface-name] hierarchy level. You can run a BERT on only one interface per PIC at a time.


Due to hardware limitations of the framer used in IQ PICs, BERT is not supported in unframed mode on the interface and may return false positive results. BERT in unframed mode is supported on Enhanced IQ (IQE) PICs.

Required Privilege Level


List of Sample Output

test interface t1-bert-start

Output Fields

To display the results of the BERT, use the show interfaces extensive command.

Sample Output

test interface t1-bert-start

user@host> test interface t1-bert-start t1-1/0/0