Following keys combinations are very useful while working with Cisco IOS Command Line Interface (CLI). Most important Cisco IOS Shortcut Keys are
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U = user mode prompt is: routername>
P = privileged exec mode prompt is: routername#
G = global configuration mode prompt is: routername(config)#
I = interface configuration mode prompt is: routername(config-if)#
L = virtual terminal line configuration mode prompt is: routername(config-line)#
R = router configuration mode prompt is: routername(config-router)#
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