Technical Documentation

Configuring a Gigabit Ethernet Interface

The LN1000 has eight Gigabit Ethernet interfaces that can terminate into a copper or fiber Ethernet PHY device SFP (small form-factor pluggable). Depending on the type of device into which you are terminating these Gigabit Ethernet interfaces, you can configure them to operate in SGMII or 1000Base-X mode. When configured in SGMII mode, you can run ports speeds of 10/100/1000 Mbs in full or half duplex modes. When configured in 1000Base-X mode, you can run these ports in 1000 Mbs mode. Use the mac-mode statement in Chapter 7 to configure these options.

The LN1000-V rear transition module (RTM) supports both copper and fiber SFPs.

  • If you are running an LN1000 with the LN1000-V RTM and are using copper SFPs, configure the mac-mode to SGMII.
  • If you are running an LN1000 with the LN1000-V RTM and are using fiber SFPs, configure the mac-mode to 1000Base-X.

JUNOS Software uses the following defaults:

  • mac-mode set to 1000Base-X
  • auto-negotiation set to ON

To add or change mac-mode fields:

set interfaces ge-0/0/1 gigether-options mac-mode sgmii|1000base-x

If you want to delete mac-mode, use the following command:

delete interfaces ge-0/0/1 gigether-options mac-mode

If you want to run in a different configuration to match your topology, you can use the existing JUNOS auto-negotiation and link-speed statements and the new mac-mode statement.

To enable or disable autonegotiation, use the following commands:

  • Enabling autonegotiation:
    set interface ge-x/x/x gigether-options autoneg
  • Disabling autonegotiation
    set interface ge-x/x/x gigether-options no-autoneg

The delete interface ge-x/x/x gigether-options autoneg command does not disable autonegotiation. The delete command is not applicable for this option.

To change the mac-mode fields:

delete interfaces ge-0/0/1 gigether-options mac-mode

Both the speed and link-mode attributes must be modified together in the same configuration commit in order for either change to take effect.


Published: 2010-02-18