Commands by drizzt (2)

  • 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 $net$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 $net$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 $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; test $i = 30 && break ; i=$(expr $i + 1) ; done and so on. Show Sample Output

    net=DTAG-DIAL ; for (( i=1; i<30; i++ )); do whois -h $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done
    drizzt · 2009-08-01 05:28:19 0
  • 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 #!/bin/sh dig +short txt ${1} and run it like ./ unix were your first option ($1) will be used as search term. Show Sample Output

    dig +short txt <keyword>
    drizzt · 2009-07-31 16:08:59 33

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