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:: Question ?
What is the use of loopback
interface and why should people use/create
them ? I see many configs in which
loopback addresses are assigned.
MD.
MUNEER AHMED, STC
In EIGRP and OSPF routing protocols,
a router is identified by its Router
ID. If loopback interfaces are not
configured, the Router ID is the highest
IP address of any physical interface
of that router. The disadvantage of
using physical addresses to define
the Router ID is, A physical interface
on a router might go down at any time
and come up again. If the physical
interface with the highest IP address
goes down, then the Router ID will
change. To keep the Router ID consistent,
logical interfaces called as Loopback
interfaces are created which will
never go down and hence the Router
ID remains consistant
