Capture DNS queries with DNSQuery Sniffer

DNSQuery Sniffer is a free Windows application that captures your computer DNS queries, the program is useful to troubleshoot name resolution complications and check if a domain name is being blacklisted by your ISP DNS. There is no need to install the program, you can run it in portable mode and carry it with you on a USB thumbdrive.

When you run DNSQuery Sniffer for the first time you will shown the available network adapters in your computer, including virtual host components presented as a separate network cards. Your initial choice of capture options will be set as default, to change them later on you will have to access Options>Capture Options or click F9, there are shortcuts to access many of the functions.

DNSQuery Sniffer capturing DNS queries

DNSQuery Sniffer capturing DNS queries

I recorded my DNS queries while on a VPN and it worked perfectly well. A VPN encrypts data in transit over the Internet but recording takes place before DNS queries leave the router. Another use for this program could be for a system administrator to spy on network users, if you are using a portable VPN on an Internet Cafe, DNSQuery Sniffer is one of the many tools a computer admin can deploy to monitor in real time at what sites you are visiting.

Some of the details recorded include Host name and port (for example: pagead2.googlesyndication.com:54630), DNS query time stamp, request time and response time, reverse DNS lookup, IPv6 server address, destination IP address and many others. I noticed that most of the requests only show hostname and port, itemised displayed details will depend on what server you visit.

While I was recording outbound queries on my computer I was able to see Google Adsense and Facebook queries created by the plugins embedded in the website I just visited. Logs can become huge within a couple of recording hours, they can be exported as CSV/XML or HTML file and import them into a spreadsheet for processing.

This tool will be useful for system administrators. Home users without logging needs might prefer to troubleshoot DNS problems with another freeware called DNS Benchmark.

Visit DNSQuery Sniffer homepage

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