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Hierarchy Level


Configure the duration of a BERT test. Applies to E1, E3, T1, and T3 interfaces, and to E1, E3, T1, and T3 partitions on the channelized interfaces (CE1, CT1, DS3, OC3, OC12, OC48, STM1, STM4, and STM16).

E1 and T1 IQ, IQE, and standard interfaces support an extended BERT period range, up to 86,400 seconds (24 hours).


When configuring CE1 or CT1 interfaces on 10-port Channelized E1/T1 IQE PICs, the bert-period statement must be included at the [edit interfaces ce1-fpc/pic/port] or [edit interfaces ct1-fpc/pic/port] hierarchy level as appropriate.


seconds—Test duration. Range and default values vary by interface type.


    • PIC-dependent—Normal BERT period: either 1 through 239 seconds or 1 through 240 seconds

    • PIC-dependent—Extended BERT period: from 1 through 86,400 seconds


    • Normal BERT period: 10 seconds

    • Extended BERT period (on supported E1 interfaces): 10 seconds

    • Extended BERT period (on supported T1 interfaces): 240 seconds

Required Privilege Level

interface—To view this statement in the configuration.

interface-control—To add this statement to the configuration.

Release Information

Statement introduced before Junos OS Release 7.4.