Network Failure

Network failure is by far the most common router problem, even though, technically, the router itself hasn't failed—the circuit has. Backhoes digging in the wrong spot cause any number of circuit outages, and you'll never fix those yourself. Before you blame the telco or ISP, however, you can do several things to rule out problems on your end and maybe even quickly fix the problem without outside help.

Most network administrators are fairly skilled at troubleshooting Ethernet problems. Is there a link light? Did the duplex setting change? Is the switch port bad, or did someone trip on the cable and break the little plastic thingamajig on the end? The time-honored ritual of replacing cables and switching ports solves most Ethernet ...

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