Network-Tools doesn't offer nearly the plethora of tools as does DNS Stuff, but all of their tools are free for the using. Here you will find quick access to: Ping, Trace Route, Whois, Lookup, DNS Records, Blacklist Check, URL Decode/Encode, Email Test, and more.
The Express test will give you the fastest results as it does a combo of Traceroute, DNS, and Whois testing. The report back from that test will often give you the information you need to immediately begin your first steps of troubleshooting the external connection to your route.
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