Querying DNS With Nslookup
Look up records and diagnose name-resolution problems.
What Nslookup Does
nslookup (name server lookup) queries DNS directly, letting you ask "what IP does this name resolve to?" and inspect DNS records. While ping by name tests DNS indirectly, nslookup tests it on purpose and in detail. It is the primary command-line tool for diagnosing name-resolution problems, available on Windows, Linux, and macOS.
nslookup example.comWhy Query DNS Directly
Many outages are really DNS problems in disguise: a site "down" that is actually unresolvable, or one that points to the wrong server. Querying DNS directly with nslookup separates name resolution from connectivity. If nslookup returns the right IP, DNS is fine and you look elsewhere; if it fails, you have found the cause.
All lessons in this course
- Testing Reachability With Ping
- Mapping the Path With Traceroute
- Viewing Settings With Ipconfig
- Querying DNS With Nslookup