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monitor interface error



You can use the monitor interface error command to display errors in packet headers that are transmitted through all network interfaces. Use the following options at the end of the command for more specific information.



(Optional) Displays packet header errors for a specified interface or interfaces. If an interface is not specified, all interfaces are monitored.

Required Privilege Level


Output Fields

Table 1 lists the output fields for the monitor interface error command.

Table 1: monitor interface error Output Fields

Field Name

Field Description

CRC Errors

Displays the number of CRC errors on the selected interfaces since you started monitoring.

Corr errors

Displays the number of FEC corrected errors since monitoring began.

FEC Mode

Displays the FEC mode configured on the interface.

Interface Name

Displays the interface name.

Link Flaps

Displays the number of link flaps observed during the current monitoring session.

Link Status

Displays the interface link status.

PCS bit err sec

Displays the PCS bit error count.

PCS err blk sec

Displays the number of PCS error blocks found.


Displays the pre-FEC bit error rate (BER). This is used to monitor the condition of an optical transport network (OTN) link.


Displays the speed of the interface.


Displays the time since the error table was cleared/updated.

Uncorr errors

Displays the number of FEC uncorrected errors since monitoring began.

Sample Output

monitor interface error

monitor interface error et-1/0/1

Release Information

Command introduced in Junos OS Evolved Release 22.2R1.