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Well, not when there is NO physical connection anymore, but if you have _some_ connection through one of multiple redundant links, the IP is still available.<br />
On normal physical interfaces, if a link goes down, the IP is disabled, so you can no longer reach the router through it. This does not happen with loopbacks, as they are always &quot;up&quot; (unless manually shut down).
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Well, not when there is NO physical connection anymore, but if you have _some_ connection through one of multiple redundant links, the IP is still available.
On normal physical interfaces, if a link goes down, the IP is disabled, so you can no longer reach the router through it. This does not happen with loopbacks, as they are always "up" (unless manually shut down).

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Hi,<br />
What is the importance of <b>Loopback IP address </b>configuration.<br />
I have studued that if physical connectivity gets lost &nbsp;then we can access Router using Loopback Address, what is the Logic behind that, how we can access with out physical ocnnectivity.<br />
<br />
Regards<br />
ramu<br />
<br />

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Hi,
What is the importance of Loopback IP address configuration.
I have studued that if physical connectivity gets lost  then we can access Router using Loopback Address, what is the Logic behind that, how we can access with out physical ocnnectivity.

Regards
ramu



Loopback Interface in Router

A router is a networking device that forwards data packets between computer networks. Routers perform the "traffic directing" functions on the Internet. The most familiar type of routers are home and small office cable or DSL routers that simply pass data, such as web pages, email, IM, and videos between computers and the Internet. More sophisticated routers, such as enterprise routers, connect large business or ISP networks up to the powerful core routers that forward data at high speed along the optical fiber lines of the Internet backbone. Though routers are typically dedicated hardware devices, use of software-based routers has grown increasingly common.