Commands by knassery (3)

  • Tshark to Generate Top Talkers by #TCP conv started per second.

    #_connects src_IP dst_IP When_It_Happened_Secs Show Sample Output


    -1
    tshark -qr [cap] -z conv,tcp | awk '{printf("%s:%s:%s\n",$1,$3,$10)}' | awk -F: '{printf("%s %s %s\n",$1,$3,substr($5,1,length($5)-10))}' | sort | uniq -c | sort -nr
    knassery · 2012-10-16 06:39:01 5
  • Show me a histogram of the busiest minutes in a log file:

    Busiest seconds: cat /var/log/secure.log | awk '{print substr($0,0,15)}' | uniq -c | sort -nr | awk '{printf("\n%s ",$0) ; for (i = 0; i<$1 ; i++) {printf("*")};}' Show Sample Output


    17
    cat /var/log/secure.log | awk '{print substr($0,0,12)}' | uniq -c | sort -nr | awk '{printf("\n%s ",$0) ; for (i = 0; i<$1 ; i++) {printf("*")};}'
    knassery · 2009-07-24 07:20:06 12
  • Graph # of connections for each hosts.

    Written for linux, the real example is how to produce ascii text graphs based on a numeric value (anything where uniq -c is useful is a good candidate). Show Sample Output


    54
    netstat -an | grep ESTABLISHED | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }'
    knassery · 2009-04-27 22:02:19 26

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