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loopback (Aggregated Ethernet, Fast Ethernet, and Gigabit Ethernet)


Hierarchy Level

For QFX Series and EX Series:

For SRX Series Firewalls and vSRX Virtual Firewall:


For aggregated Ethernet, Fast Ethernet, Gigabit Ethernet, and 10-Gigabit Ethernet interfaces, enable or disable loopback mode.

  • By default, local aggregated Ethernet, Fast Ethernet, Tri-Rate Ethernet copper, Gigabit Ethernet, and 10-Gigabit Ethernet interfaces connect to a remote system.

  • IPv6 Neighbor Discovery Protocol (NDP) addresses are not supported on Gigabit Ethernet interfaces when loopback mode is enabled on the interface. That is, if the loopback statement is configured at the [edit interfaces ge-fpc/pic/port gigether-options] hierarchy level, an NDP address cannot be configured at the [edit interfaces ge-fpc/pic/port unit logical-unit-number family inet6 address] hierarchy level.


By default, loopback is disabled.

Required Privilege Level

interface—To view this statement in the configuration.

interface-control—To add this statement to the configuration.

Release Information

Statement introduced before Junos OS Release 7.4.

Statement introduced in Junos OS Release 12.2 for ACX Series Universal Metro Routers.

Statement modified in Junos OS Release 9.2 for the SRX Series.