交换机端口

[hexi_zhengfawei_jhj-probe]debug port link-diag slot 1 0 15 0

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 Slot:1/port/tgid:14 operation record, need be translated with code and line num

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 [0]:PID=176 TName=stpd Line=5265  06/26/2016 02:04:49:360

     m0=62602 m1=521 m2=4609   IOCTL_ETHERNET_STG_SET_PORT_STATE

 [1]:PID=99 TName=kifup Line=14659  06/26/2016 02:04:19:282

     m0=4 m1=0 m2=0   drv_port_platform_event_if_notify

 [2]:PID=4089 TName=ifmgr Line=3215  06/26/2016 02:04:19:238

     m0=1 m1=0 m2=0   drv_port_enable_hardware_set

 [3]:PID=4089 TName=ifmgr Line=3314  06/26/2016 02:04:19:236

     m0=1 m1=2 m2=0   drv_port_enable_set

 [4]:PID=4089 TName=ifmgr Line=4734  06/26/2016 02:04:19:236

     m0=0 m1=264 m2=2   IOCTL_COMMON_UNDO_SHUTDOWN

 [5]:PID=176 TName=stpd Line=5265  06/26/2016 02:04:15:005

     m0=63818 m1=521 m2=4609   IOCTL_ETHERNET_STG_SET_PORT_STATE

 [6]:PID=99 TName=kifup Line=14654  06/26/2016 02:04:14:994

     m0=1 m1=0 m2=0   drv_port_platform_event_if_notify

 [7]:PID=4089 TName=ifmgr Line=3215  06/26/2016 02:04:14:991

     m0=2 m1=0 m2=0   drv_port_enable_hardware_set

 [8]:PID=4089 TName=ifmgr Line=3314  06/26/2016 02:04:14:989

     m0=2 m1=1 m2=0   drv_port_enable_set

 [9]:PID=4089 TName=ifmgr Line=4714  06/26/2016 02:04:14:989

     m0=0 m1=264 m2=1   IOCTL_COMMON_SHUTDOWN

 [10]:PID=176 TName=stpd Line=5265  06/26/2016 01:41:21:360

     m0=64586 m1=521 m2=4609   IOCTL_ETHERNET_STG_SET_PORT_STATE

 [11]:PID=99 TName=kifup Line=14659  06/26/2016 01:40:50:690

     m0=4 m1=0 m2=0   drv_port_platform_event_if_notify

端口down的原因是啥？