现象描述端口不能正常up。与其他产品对接出现一端up，一端down。没有接线，端口指示灯一直常亮。端口up一段时间又会down掉，不稳定。可能原因本端和对端端口配置不正确。combo端口的光电模式设置不正确。端口故障。操作步骤检查本端和对端端口配置是否正确。正确的端口配置才能保证端口正常up，判断对接两端端口的速率、双工、协商模式是否一致，两端工作模式必须一致，如果两端工作模式一端自协商一端强制，则强制端up、自协商端down;如果不一致请配置一致。如下命令为查询本端端口的配置。[sysname-gigabitethernet0/0/1] display this interface
gigabitethernet0/0/1 current state : up
line protocol current state : down
description : huawei, sysname, gigabitethernet0/0/1 interface, route port
the maximum transmit unit is 1500 bytes, hold timer is 10(sec)
internet protocol processing : disabled
ip sending frames' format is pktfmt_ethnt_2, hardware address is 4862-7605-5209
media type is twisted pair, loopback not set, promiscuous mode not set
1000mb/s-speed mode, full-duplex mode, link type is auto negotiation
qos max-bandwidth : 1000000 kbps
如果设备为combo口，请正确设置端口为电口或者光口。combo口为光电互斥口，两个端口同时只能使用一个，设置为电口只能作为电口使用，设置为光口只能作为光口使用。通过如下方式判断端口是否故障。若端口故障则需要根据端口位置更换插卡或者整机。
使用此端口出现故障，更换到其他端口观察现象描述是否仍然存在，如果故障消失，说明原端口异常。同一台设备的两个端口对接是否两个端口也不能正常up，如果不能正常up，说明原端口异常。针对有问题的端口，使用自环命令进行测试，测试是否pass，若测试失败则该端口异常。测试通过显示内容为：[sysname-diagnose] test loopback interface 0 0 1 254
sysname %%01phy/2/statusup(l): gigabitethernet0/0/1 changed status toup.
test ......
interface testing succeeded.
sysname %%01phy/2/statusdown(l): gigabitethernet0/0/1 changed status to down.
测试失败显示内容为：[sysname-diagnose] test loopback interface 0 0 1 254
test .....
interface testing failed.
如果端口存在fcs计数错误，若网线接触良好或者更换新网线后依旧存在fcs计数错误，说明原端口异常。[sysname] display interface gigabitethernet0/0/1
gigabitethernet0/0/1 current state : down
line protocol current state : down
description : huawei, sysname, gigabitethernet0/0/1 interface, route port
the maximum transmit unit is 1500 bytes, hold timer is 10(sec)
internet protocol processing : disabled
ip sending frames' format is pktfmt_ethnt_2, hardware address is 8038-bc12-484d
media type is twisted pair, loopback not set, promiscuous mode not set
unknown-speed mode, unknown-duplex mode, link type is auto negotiation
qos max-bandwidth : 1000000 kbps
output queue : (urgent queue : size/length/discards) 0/50/0
output queue : (frag queue : size/length/discards) 0/1000/0
output queue : (protocol queue : size/length/discards) 0/1000/0
output queue : (fifo queue : size/length/discards) 0/256/0
last 300 seconds input rate 0 bytes/sec, 0 packets/sec
last 300 seconds output rate 0 bytes/sec, 0 packets/sec
input: 0 packets, 0 bytes
0 unicasts, 0 broadcasts, 0 multicasts, 0 pauses
0 overruns, 0 runts, * jumbos, 0 fcs errors
* length errors, 0 code errors, * align errors
0 fragment errors, 0 giants, 0 jabber errors
* dribble condition detected, * other errors
output: 0 packets, 0 bytes
0 unicasts, 0 broadcasts, 0 multicasts, 0 pauses
0 underruns, * runts, * jumbos, * fcs errors
* fragment errors, 0 giants, * jabber errors
0 collisions, 0 late collisions
0 ex. collisions, 0 deferred, 0 other errors