Huawei Router

How to Locate CRC Errors on E1 Channels Configured on the CPOS Interface of an NE20E-S

Issue Description

Device model: NE20E-S8
Software version: V800R00X
Symptom: The E1 X unframed command is run on CPOS 0/2/0 of the controller to generate multiple E1 channels. Some channels encounter a CRC error.

[~HUAWEI-Cpos0/2/1]dis in Serial0/2/1/30:0
Serial0/2/1/30:0 current state : UP (ifindex: 62072)
Line protocol current state : UP
Last line protocol up time : 2017-04-05 18:31:23
Route Port,The Maximum Transmit Unit is 1500, Hold timer is 0(sec)
Derived from Cpos 0/2/1 e1 30, Unframed mode, baudrate is 2048000 bps
Internet Address is
Link layer protocol is PPP
LCP opened, IPCP opened
PPP negotiated peer ip address is
clock master, loopback local
Scramble disabled
Current system time: 2017-04-05 18:36:38
Alarm: none
Statistics last cleared:2017-04-05 18:31:39
Traffic statistics:
Last 10 seconds input rate 0 bits/sec, 0 packets/sec
Last 10 seconds output rate 0 bits/sec, 0 packets/sec
Input: 9 packets, 329 bytes
Input error: 0 shortpackets, 0 longpackets, 3 CRC, 14 lostpackets
Output: 9 packets, 329 bytes
Output error: 0 lostpackets
Output error: 0 overrunpackets, 0 underrunpackets
Last 10 seconds input utility rate:  0.00%
Last 10 seconds output utility rate: 0.00%

Huawei NE20E-S8


1. Check whether the CRC modes on both ends are consistent.

2. Check whether the parameters of the optical module are within the normal range.
display optical-module extend information controller cpos interface-number

3. Perform a loopback local test to check whether boards on the local device (device A) work properly.

4. Perform a loopback remote test on the interface of device B to check whether the optical module and fibers between device A and device B work properly.

For details about the test procedure, see the attachment. If a lot of CRC errors occur in the test, engineers can locate the problem.

If the problem persists, collect information about the display diag command output, log.log and diag.log files in the flash card, and the test records. Then, contact technical support.