User guide

These limitations do not apply to channelized IQ interfaces. For information about BERT
capabilities on channelized IQ interfaces, see Channelized IQ and IQE Interfaces Properties.
Starting and Stopping a BERT Test
Before you can start the BERT test, you must disable the interface. To do this, include
the disable statement at the [edit interfaces interface-name] hierarchy level:
[edit interfaces interface-name]
disable;
After you configure the BERT properties and commit the configuration, begin the test by
issuing the test interface interface-name interface-type-bert-start operational mode
command:
user@host> test interface interface-name interface-type-bert-start
The test runs for the duration you specify with the bert-period statement. If you wish to
terminate the test sooner, issue the test interface interface-name interface-type-bert-stop
command:
user@host> test interface interface-name interface-type-bert-stop
For example:
user@host> test interface t3-1/2/0 t3-bert-start
user@host> test interface t3-1/2/0 t3-bert-stop
To view the results of the BERT test, issue the show interfaces extensive | find BERT
command:
user@host> show interfaces interface-name extensive | find BERT
For more information about running and evaluating the results of the BERT procedure,
see the CLI Explorer.
NOTE: To exchange BERT patterns between a local router and a remote
router, include the loopback remote statement in the interface configuration
at the remote end of the link. From the local router, issue the test interface
command.
Example: Configuring Bit Error Rate Testing
Configure a BERT test on a T3 interface. In this example, the run duration lasts for 120
seconds. The configured error rate is 0, which corresponds to a bit error rate of 10
–0
(1
error per bit). The configured bit pattern of all-ones-repeating means that every bit the
interface sends is a set to a value of 1.
[edit interfaces]
t3-1/2/0 {
t3-options {
bert algorithm all-ones-repeating;
bert-error-rate 0;
bert-period 120;
91Copyright © 2014, Juniper Networks, Inc.
Chapter 6: Interface Diagnostics