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Configuring Ethernet Loopback Capability


By default, local aggregated Ethernet, Fast Ethernet, Tri-Rate Ethernet copper, Gigabit Ethernet, and 10-Gigabit Ethernet interfaces connect to a remote system. To place an interface in loopback mode, include the loopback statement:


If you configure a local loopback on a 1-port 10-Gigabit IQ2 and IQ2-E PIC using the loopback statement at the [edit interfaces interface-name gigether-options] hierarchy level, the transmit-path stops working, causing the remote end to detect a link down.

To return to the default—that is, to disable loopback mode—delete the loopback statement from the configuration:

To explicitly disable loopback mode, include the no-loopback statement:

You can include the loopback and no-loopback statements at the following hierarchy levels:

  • [edit interfaces interface-name aggregated-ether-options]

  • [edit interfaces interface-name ether-options]

  • [edit interfaces interface-name fastether-options]

  • [edit interfaces interface-name gigether-options]