The dummy interface is really a little exotic, but rather useful nevertheless. Dummy interfaces are much like the Loopback interface, except you can have as many as you want.
Dummy interfaces can be used as interfaces that always stay up (in the same fashion to loopbacks in Cisco IOS), or for testing purposes.
A Dummy interface is always up, thus it could be used for management traffic or as source/destination for and IGP like BGP so your internal BGP link is not dependent on physical link states and multiple routes can be chosen to the destination. A Dummy Interface should always be preferred over a Loopback interface.
Configure dummy interface <interface> with one or more interface addresses. Address can be specified multiple times as IPv4 and/or IPv6 address, e.g. 192.0.2.1/24 and/or 2001:db8::1/64
set interfaces dummy dum10 address 192.0.2.1/24 set interfaces dummy dum10 address 192.0.2.2/24 set interfaces dummy dum10 address 2001:db8::ffff/64 set interfaces dummy dum10 address 2001:db8:100::ffff/64