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Basic Settings on a Router (1.1.3) > Cisco Networking Academy's Introduction to Routing Concepts | Cisco Press
David Bombal on Twitter: "Paul tries to configure a loopback interface on a Cisco router with a loopback address. The router, however, displays the following error. Why is this configuration invalid? #CCNA #
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IPSec VPN connection to Cisco ASA with loopback interfaces on internal GRE routers - Discussions - Sophos Firewall - Sophos Community
![Fred de Jonge | Cisco Router - Site to site configuration on a router with 2 BGP interfaces and 1 Loopback interface with External IP. Fred de Jonge | Cisco Router - Site to site configuration on a router with 2 BGP interfaces and 1 Loopback interface with External IP.](https://i0.wp.com/freddejonge.nl/wp-content/uploads/2012/05/image1.png)
Fred de Jonge | Cisco Router - Site to site configuration on a router with 2 BGP interfaces and 1 Loopback interface with External IP.
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What is Loopback interface in Cisco Router and what is use of loopback interface how to configure Loopback interface
![cisco - Whats's the function of a loopback interface in routing protocols? - Network Engineering Stack Exchange cisco - Whats's the function of a loopback interface in routing protocols? - Network Engineering Stack Exchange](https://i.stack.imgur.com/TLEFV.png)
cisco - Whats's the function of a loopback interface in routing protocols? - Network Engineering Stack Exchange
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