H3C Switch Optical Port Speed

Optical port speed on H3C switches is typically set to 1000 Mbps full-duplex by default, but can be adjusted using the speed command in Ethernet port view, with considerations for duplex mode and auto-negotiation.

Default Behavior of Optical Ports

• A 1000 Mbps optical Ethernet port operates in full-duplex mode by default, even if auto-negotiation is enabled .
• A 100 Mbps optical port supports only 100 Mbps and should also be configured in full-duplex mode to avoid negotiation errors .
• 10 Gbps optical ports only support 10 Gbps and cannot be set to lower speeds .

Configuring Optical Port Speed

1. Enter system view:

   system-view

2. Enter the Ethernet port view for the optical interface:

   interface GigabitEthernet1/0/1

3. Set the port speed:

   speed {10 | 100 | 1000 | auto}

   • For 1000 Mbps optical ports, use 1000 or auto.
   • For 100 Mbps optical ports, use 100.
   • The auto option enables auto-negotiation with the peer port .
4. Set duplex mode (if needed):

   duplex {full | auto}

   • Optical ports do not support half-duplex .
   • Full-duplex is recommended for all optical ports to ensure correct negotiation .
5. Enable the port:

   undo shutdown

Special Considerations for Combo Ports

• Combo ports integrate an optical and a copper interface, but only one can be active at a time .
• Use the following commands to select the active medium:

  combo enable fibercombo enable copper

• Ensure the optical module is properly inserted and compatible with the switch .

Verification

• Check the port status and speed:

  display interface GigabitEthernet1/0/1 This command shows link status, negotiated speed, duplex mode, and transceiver type .

• For a summary of all ports:

  display interface brief

Best Practices

• Always configure optical ports in full-duplex mode.
• Use auto-negotiation when connecting to devices that support it, but manually set speed if connecting to legacy equipment.
• For combo ports, disable traffic before switching between fiber and copper to avoid link conflicts .
• Verify that the SFP module is certified for H3C devices to ensure proper speed negotiation . By following these steps, you can reliably adjust and verify the speed of optical ports on H3C switches while maintaining network stability and compatibility.