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test interface e3-bert-start



Release Information

Command introduced before Junos OS Release 7.4.


Start a bit error rate test (BERT) on an E3 interface.


e3-fpc/pic/portE3 interface name.

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 e3-bert-start

Output Fields

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

Sample Output

test interface e3-bert-start

user@host> test interface e3-bert-start e3-1/0/0