What online troubleshooting tools do you use on a daily basis? [closed]

Question

What online networking troubleshooting tools do you find indispensable and why?

The one that I use the most often is network-tools.com because it does ping, DNS lookups, tracetorutes, and email SMTP testing but I'm always looking for better tools.

Answer 1

I have used the following things quite regularly.
While the primary points are noted besides each reference,
there are sometime quite a few secondary uses too.

• OpenDNS -- to identify DNS problems
• NMAP -- which has just moved to the 5.0 version
• InternetFrog, APNIC -- to lookup IP, Domain, Whois
• The Firefox ShowIP extension -- while I am browsing
• dig from DNSTools
• Ethernet OUI Listing lookup -- identify network interfaces; to guess equipment running them
• SysinternalsSuite tools -- TCPView -- see whats connected from my machine

Answer 2

Whenever I have mail or DNS questions, I always turn to a quick run-down with IntoDNS. Not only does it spot problems, but it also gives suggestions for remediation. Very handy when you're hurried and could easily overlook a detail.

Answer 3

I use www.geektools.com, but I think I'm switching to your choice, network-tools.com, because it tells me my ip address right off the bat. Thanks.

Answer 4

I use nmap regularly. It is most useful to find out what kind of device is behind an IP address and what services the device offers.

Answer 5

http://iptools.com/ has some array of tools.

Also, http://www.robtex.com/ is good for non trivial stuff (like finding out some of the host names on a given IP)