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May 19, 2015 - A Look At The New Commandlinefu
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Commands tagged dns from sorted by
Terminal - Commands tagged dns - 31 results
dig -x {IP}
host {checkIp or hostname} [dns server]
2009-12-21 11:48:00
User: mccalni
Functions: host
Tags: IP reverse dns

I'm just a simple programmer. I find dig too verbose. host tells me alias(es) and IP address in a quick to grok format with nothing special to remember for input parameters.

With thanks to http://www.cyberciti.biz/faq/how-to-test-or-check-reverse-dns/

check_dns_no() { for i in $* ; do if `wget -O - -q http://www.norid.no/domenenavnbaser/whois/?query=$i.no | grep "no match" &>/dev/null` ; then echo $i.no "available" ; fi ; sleep 1 ;done }
2009-09-30 21:17:33
User: xeor
Functions: echo grep sleep
Tags: wget dig dns

Mostly for Norwegians, but easily adoptable to others. Very handy if you are brainstorming for a new domainname.

Will only display the available ones..

You can usually do this better with dig, but if you dont have dig, or the TLD only have an online service to check with, this will be usefull..

nmap -R -sL | awk '{if($3=="not")print"("$2") no PTR";else print$3" is "$2}' | grep '('
2009-09-02 16:33:15
User: netsaint
Functions: awk grep
Tags: nmap dns

This command uses nmap to perform reverse DNS lookups on a subnet. It produces a list of IP addresses with the corresponding PTR record for a given subnet. You can enter the subnet in CDIR notation (i.e. /24 for a Class C)). You could add "--dns-servers x.x.x.x" after the "-sL" if you need the lookups to be performed on a specific DNS server.

On some installations nmap needs sudo I believe. Also I hope awk is standard on most distros.

dig google.com
2009-08-28 04:32:52
User: unixbhaskar
Functions: dig
Tags: dns

It is a much better tool then nslookup for getting information about the any site.It has got better capability too.For reverse information please use the switch "-x" and the ip address.

dig +short txt <keyword>.wp.dg.cx
2009-07-31 16:08:59
User: drizzt
Functions: dig

Query Wikipedia by issuing a DNS query for a TXT record. The TXT record will also include a short URL to the complete corresponding Wikipedia entry.You can also write a little shell script like:

$ cat wikisole.sh


dig +short txt ${1}.wp.dg.cx

and run it like

./wikisole.sh unix

were your first option ($1) will be used as search term.