@iwalker Very nice recap of dig features. I got some of that from the man page. Apparently nslookup is old and has some bugs in some OSs, according to what I read.
At first I was putting the ‘cname’ or ‘mx’ part in front of the domain name. You can imagine that didn’t work out.
I don’t understand DNS very well, but from what I gather, its basics are simple. Can you point me to a kind of 5-minute explanation of how it works? This is my guess:
(1) When anyone sends a DNS query, he should target a DNS name server using DNS internet protocol. (But which name server should he query if he is a web client trying to get an IP address for TCP/IP requests?)
(2) In response, the name server he queries will send back an IP address (or set of IP addresses?). If the name server doesn’t know, it will forward the request to another name server, and so on until the request arrives at a name server that knows.
(3) Somehow (directly from the name server that knows? or backwards through the chain of requestees?) the IP address (or set of IP addresses?) gets back to the original querier.
Is that correct? Could you please fill out the blanks in the above 1-minute overview?
If I query doc.mashweb.club or mashweb.club to get a name server by using the ‘ns’ type, what is the particular name server in the response? Is it the name server that knows the IP address(es)?
I wish I could see an annotation of a dig response with links and less cryptic labels. For instance, when my shell executes the command ‘dig @8.8.8.8 doc.mashweb.club ns’ I get a column full of the abbreviation or word ‘IN’. Does that refer to an ISO country code?
I just bought a cheap but neat little app for my iPhone that makes things easier to understand for me. I still need to learn some lingo, but it’s comforting to an old guy like me to see simple things kept simple. The app is available at Network Utility on the App Store . It even shows the suspicious answers when digging doc.mashweb.clug: the CNAME record and 2 A records. By contrast, the host command was about as cryptic as the dig command.