![Huawei V200R001C01 Скачать руководство пользователя страница 119](http://html.mh-extra.com/html/huawei/v200r001c01/v200r001c01_troubleshooting-manual_168099119.webp)
Item
Description
Follow-up Operation
Check whether the
loopback function
is configured on
the local and
remote interfaces.
Run the
display this
command
in the CE1 interface view to
check whether the loopback
function is configured on the
interface. If
loopback local
,
loopback payload
, or
loopback remote
is displayed,
the loopback function is
configured on the interface. The
loopback function will cause the
interface to alternate between
Up and Down states. Therefore,
disable the loopback function
after loopback detection is
complete.
NOTE
After the
display controller e1
command is run in the system
view, if the
Alarm State
field is
displayed as
Alarm-Indication-
Signal
, the loopback function may
be configured on the interface.
If the loopback function has
been configured on the local and
remote interfaces, run the
undo
loopback
command in the CE1
interface view to disable the
loopback function.
If "E1 1/0/0 current state : DOWN" is still displayed, go to step 4.
l
If "E1 1/0/0 current state : UP" is displayed, E1 1/0/0 is in Up state. Go to step 2.
Step 2
Check that packets are sent and received on the local and remote interfaces.
NOTE
After the
display controller e1
command is run in the system view, if the
Alarm State
field is displayed
as
Remote-Alarm-Indication
, packets may be incorrectly sent or received on the local and remote
interfaces.
Run the
debugging isdn q921
,
terminal debugging
, and
terminal monitor
commands in
sequence to check sent packets. In the command output,
U->N
indicates a direction from the
user-side interface to the network-side interface, and
Len
indicates the SABME frame length.
The correct SABME frame length is 3 bytes and the contents of a SABME frame is 00 01 7F or
02 01 7F.
l
If the following information is displayed, the length and contents of the sent SABME frames
are incorrect. Restart or replace the device.
<Huawei>
Oct 12 2007 11:54:42.240.1+08:00 Huawei Q921/7/Q921_Debug:
Serial1/0/0:15
U->N Len=7 00 01 7F 00 00 00 00
U->N sapi=00 tei=00 c/r=0 SABME p=1
<Huawei>
Oct 12 2007 11:54:43.240.1+08:00 Huawei Q921/7/Q921_Debug:
Serial1/0/0:15
U->N Len=7 00 01 7F 00 00 00
00
U->N sapi=00 tei=00 c/r=0 SABME p=1
<Huawei>
Oct 12 2007 11:54:44.240.1+08:00 Huawei Q921/7/Q921_Debug:
Huawei AR2200-S Series Enterprise Routers
Troubleshooting
5 WAN
Issue 01 (2012-01-06)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
110