Network does not connect to Internet after power off reboot

Power supply due to the failure of sudden power, and soon restore power, restart the network equipment, hardware devices are also normal operation, but the network can not intervene in the Internet.

This may be due to an imperfect software configuration that makes it impossible for a dynamic routing protocol to establish a link relationship because the no shutdown command cannot be saved in router interface mode.

This situation can be in a globally configured mode, to the router interface configuration mode, and then use the no shutdown command to activate the physical interface. Observe the routing table information, generally after 2 seconds, the network can return to normal. can be excluded.