Commands using whois (16)

  • Check if a domain is available and get the answer in just one line

    Returns nothing if the domain exists and 'No match for domain.com' otherwise.


    6
    whois domainnametocheck.com | grep match
    Timothee · 2009-08-11 13:33:25 11
  • Block all FaceBook traffic


    4
    ASN=32934; for s in $(whois -H -h riswhois.ripe.net -- -F -K -i $ASN | grep -v "^$" | grep -v "^%" | awk '{ print $2 }' ); do echo " blocking $s"; sudo iptables -A INPUT -s $s -j REJECT &> /dev/null || sudo ip6tables -A INPUT -s $s -j REJECT; done
    koppi · 2016-04-08 11:30:12 59
  • Check if a domain is available for purchase

    A quick alias to check if a domain is already registered or if it's available for purchase. Show Sample Output


    4
    function canibuy { whois "$1" 2>/dev/null | grep -q 'Registrant' && echo "taken" || echo "available" }
    tyzbit · 2023-06-21 15:01:25 138
  • Produces a list of when your domains expire

    Create a text file called domainlist.txt with a domain per line, then run the command above. All registries are a little different, so play around with the command. Should produce a list of domains and their expirations date. I am responsible for my companies domains and have a dozen or so myself, so this is a quick check if I overlooked any.


    3
    cat domainlist.txt | while read line; do echo -ne $line; whois $line | grep Expiration ; done | sed 's:Expiration Date::'
    netsaint · 2010-05-02 06:49:09 6
  • Query ip pools based on successive netnames via whois

    Useful if you f.i. want to block/allow all connections from a certain provider which uses successive netnames for his ip blocks. In this example I used the german Deutsche Telekom which has DTAG-DIAL followed by a number as netname for the dial in pools. There are - as always ;) - different ways to do this. If you have seq available you can use net=DTAG-DIAL ; for i in `seq 1 30`; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done or without seq you can use bash brace expansion net=DTAG-DIAL ; for i in {1..30}; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done or if you like while better than for use something like net=DTAG-DIAL ; i=1 ; while true ; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; test $i = 30 && break ; i=$(expr $i + 1) ; done and so on. Show Sample Output


    2
    net=DTAG-DIAL ; for (( i=1; i<30; i++ )); do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done
    drizzt · 2009-08-01 05:28:19 4
  • Check to make sure the whois nameservers match the nameserver records from the nameservers themselves

    Change the $domain variable to whichever domain you wish to query. Works with the majority of whois info; for some that won't, you may have to compromise: domain=google.com; for a in $(whois $domain | grep "Domain servers in listed order:" --after 3 | grep -v "Domain servers in listed order:"); do echo ">>> Nameservers for $domain from $a Note that this doesn't work as well as the first one; if they have more than 3 nameservers, it won't hit them all. As the summary states, this can be useful for making sure the whois nameservers for a domain match the nameserver records (NS records) from the nameservers themselves. Show Sample Output


    2
    domain=google.com; for ns in $(whois $domain | awk -F: '/Name Server/{print $2}'); do echo ">>> Nameservers for $domain from $a <<<"; dig @$ns $domain ns +short; echo; done;
    laebshade · 2011-05-08 04:46:34 4
  • whois filtering the important information


    1
    whois commandlinefu.com | grep -E '^\s{3}'
    ca9lar · 2019-04-09 21:09:30 74
  • geolocalize ip country


    0
    while read line; do pais=$(whois "$line" | grep -E '[Cc]ountry') echo -n "IP=$line Pais=$pais" && echo done <listaip
    pathcl · 2010-10-25 15:39:50 21
  • List contact infomation for Domain list

    Nice neat feedback showing contact infomation for as many domains as you wish to feed it. I used a list of domains, each one on a new line as supplied by our registar, as we needed to check they were all upto date and back them up as we are updating them all.


    0
    whois -H $(cat ./list_of_domains) | awk 'BEGIN{RS=""}/Registrant/,/Registration Service Provider:/ {print} END{print "----------------\n"}'
    djsmiley2k · 2011-01-11 12:55:34 3
  • check a list of domains registered on godaddy

    Found on https://bitcointalk.org/index.php?topic=55520.0


    0
    for i in `wget -O url|grep '<a rel="nofollow"'|grep http|sed 's|.*<a rel="nofollow" class="[^"]\+" href="[^"]*https\?://\([^/]\+\)[^"]*">[^<]\+</a>.*|\1|'`;do if test -n "$(whois $i|grep -i godaddy)";then echo $i uses GoDaddy;fi;sleep 20;done
    coinbitsdotcom · 2011-12-24 19:12:18 5
  • Produces a list of when your domains expire


    0
    cat domainlist.txt | while read line; do echo -ne $line; whois $line | grep Expiration ; done | sed 's:Expiration Date::'
    jun3337 · 2013-05-13 02:55:17 8
  • Block all traffic from an Autonomous System (AS) Network (e.g. Facebook)

    Retrieves AS route prefixes for IPv4 and IPv6, aggregates the routes to the minimal set, and adds netfilter rules to reject them. Relies on two helpers: IPv4 - "aggregate" by Joe Abley (package name 'aggregate'), IPv6 - "aggregate6" by Job Snijders ( https://github.com/job/aggregate6 ) Show Sample Output


    0
    ASN=32934; for IP in 4 6; do whois -h riswhois.ripe.net \!${IP/4/g}as${ASN} | sed -n '2 p' | tr \ \\n | aggregate${IP/4/} | while read NET; do ip${IP/4/}tables -I INPUT -S ${NET} -j REJECT; done; done
    iam_TJ · 2016-05-29 09:45:34 10
  • Block all FaceBook traffic

    I don't know why you would want to echo "blocking ....", but my alternative is functionally equivalent with the extra echo.


    0
    ASN=32934;whois -H -h riswhois.ripe.net -- -F -K -i $ASN|awk '/^'$ASN'/ {if ($2 ~ /::/) {a="6"} else {a=""};b="sudo ip"a"tables -A INPUT -s "$2" -j REJECT"; print " blocking "$2;system(b)}'
    AndrewM · 2016-07-22 07:48:27 14
  • whois multiple domains

    Outputs multiple whois from a plain text file.


    -2
    for domain in `cat list_of_domains.txt`; do echo $domain; whois $domain >> output.txt; done
    pathcl · 2010-02-15 17:13:45 7
  • Whois on target and save results to file instantly

    This can be used in scripts, to find out the origin of target IP etc. Show Sample Output


    -5
    x=192.168.1.1; whois $x > $x.txt
    sxiii · 2011-01-17 03:33:49 7
  • check if commandlinefu.com got a better domain

    It would be nice if commandlinefu.com had a better domain name. Will they pick one of the above; We'll see. Show Sample Output


    -11
    whois cmd.fu;whois cmdfu.com|grep -i cmdfu
    axelabs · 2009-02-19 08:57:50 8

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Show IP Address in prompt --> PS1 var
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Determine if a command is in your $PATH using POSIX
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