I am using RFC 1035 as source, keeping to the sequence from there, regardless if you already mentioned it in your question. QR specifies whether this message is a query (0), or a response (1) OPCODE A four bit field, only valid values: 0,1,2 AA Authoritative Answer TC TrunCation (truncated due to length greater than … Read more
RFC 1035 says: MNAME The <domain-name> of the name server that was the original or primary source of data for this zone. although in practise this MNAME field in the SOA is mostly unused these days. However if you’re using DNS dynamic updates then it must refer to the name of the DNS server which … Read more
The hint (using axfr) only works if the NS you’re querying (ns1.foo.example in your example) is configured to allow AXFR requests from the IP you’re using; this is unlikely, unless your IP is configured as a secondary for the domain in question. Basically, there’s no easy way to do it if you’re not allowed to … Read more
Use sed -e “s/[[:space:]]\+/ /g” Here’s an explanation: [ # start of character class [:space:] # The POSIX character class for whitespace characters. It’s # functionally identical to [ \t\r\n\v\f] which matches a space, # tab, carriage return, newline, vertical tab, or form feed. See # https://en.wikipedia.org/wiki/Regular_expression#POSIX_character_classes ] # end of character class \+ # … Read more
This is obviously a staged Q&A, but this tends to confuse people often and I can’t find a canonical question covering the topic. dig +trace is a great diagnostic tool, but one aspect of its design is widely misunderstood: the IP of every server that will be queried is obtained from your resolver library. This … Read more
It’s the default behaviour of dig not to use the search-option. From the manual page: +[no]search Use [do not use] the search list defined by the searchlist or domain directive in resolv.conf (if any). The search list is not used by default. Edit: Just add +search to make it work, like dig +search myhost.
I am not sure why you are getting comments in the output. That is the correct set of options for the behaviour you want. Here are the same options with the same version of dig: $ dig -version DiG 9.7.3 $ dig +noall +answer google.de google.de. 55 IN A 173.194.44.216 google.de. 55 IN A 173.194.44.223 … Read more
Yes, the number there is the number of seconds left until that record expires (providing we’re not querying the authoritative nameserver). Obviously with a CNAME there’s a level of redirection, so the TTL for the A record it points to in this case may be important as well. If you wait a couple of seconds … Read more
You can use the @ syntax to look up the domain from a particular server. If the DNS server is authoritative for that domain, the response will not be a cached result. dig @ns1.example.com example.com You can find the authoritative servers by asking for the NS records for a domain: dig example.com NS
Answer The short answer to your specific question of listing CNAMEs is that you cannot without permission to do zone transfers (see How to list all CNAME records for a given domain?). That said, if your company’s DNS server still supports the ANY query, you can use dig to list the other records by doing: … Read more