光模块不工作

两台交换机，连好光模块，但指示灯不亮，是光模块配的不对吗？请老师指点！

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交换机A：

#
interface GigabitEthernet3/0/21
 port link-mode bridge
 port link-type trunk
 port trunk permit vlan all
#

GigabitEthernet3/0/21 transceiver information:
  Transceiver Type              : 1000_BASE_LX_SFP
  Connector Type                : LC
  Wavelength(nm)                : 1310
  Transfer Distance(km)         : 20(9um)
  Digital Diagnostic Monitoring : YES
  Vendor Name                   : H3C

#

GigabitEthernet3/0/21 transceiver diagnostic information:
  Current diagnostic parameters:
    Temp.(°C) Voltage(V)  Bias(mA)  RX power(dBm)  TX power(dBm)
    43         3.44        37.47     -9.48          -6.69

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交换机B：

interface Ten-GigabitEthernet1/0/28
 port link-type trunk
 port trunk permit vlan all
 dhcp snooping trust
#

Ten-GigabitEthernet1/0/28 transceiver information:
  Transceiver Type              : 1000_BASE_LX_SFP
  Connector Type                : LC
  Wavelength(nm)                : 1310
  Transfer Distance(km)         : 20(SMF)
  Digital Diagnostic Monitoring : YES
  Vendor Name                   : H3C

#

Ten-GigabitEthernet1/0/28 transceiver diagnostic information:
  Current diagnostic parameters:
    Temp.(°C) Voltage(V)  Bias(mA)  RX power(dBm)  TX power(dBm)
    48         3.40        37.62     -40.00         -6.89
  Alarm thresholds:
          Temp.(°C) Voltage(V)  Bias(mA)  RX power(dBm)  TX power(dBm)
    High  100        3.60        80.00     0.00           3.00
    Low   -40        3.00        1.00      -29.98         -15.00

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交换机A，21口光模块，经光纤，连接交换机B，28口