Commands by toxick (2)

  • list current ssh clients


    1
    netstat -tn | awk '($4 ~ /:22\s*/) && ($6 ~ /^EST/) {print substr($5, 0, index($5,":"))}'
    toxick · 2012-10-03 04:47:54 2
  • Display CPU usage in percentage

    Using the output of 'ps' to determine CPU usage is misleading, as the CPU column in 'ps' shows CPU usage per process over the entire lifetime of the process. In order to get *current* CPU usage (without scraping a top screen) you need to pull some numbers from /proc/stat. Here, we take two readings, once second apart, determine how much IDLE time was spent across all CPUs, divide by the number of CPUs, and then subtract from 100 to get non-idle time. Show Sample Output


    0
    NUMCPUS=`grep ^proc /proc/cpuinfo | wc -l`; FIRST=`cat /proc/stat | awk '/^cpu / {print $5}'`; sleep 1; SECOND=`cat /proc/stat | awk '/^cpu / {print $5}'`; USED=`echo 2 k 100 $SECOND $FIRST - $NUMCPUS / - p | dc`; echo ${USED}% CPU Usage
    toxick · 2012-10-02 03:57:51 3

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Display the end of a logfile as new lines are added to the end

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Issues a scan command on the given scsi host adapter (ex. a fibre channel adapter, in the example above on host0). Output can be watched in the messages log or in "dmesg"

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find geographical location of an ip address
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Binary clock
Like 7171, but fixed typo, uses fewer variables, and even more cryptic!

convert markdown to PDF
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vim insert current filename
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Reboot without being root
For more, See: https://github.com/noureddin/bash-scripts/blob/master/user_scripts/userpower

delete a particular line by line number in file
deletes line 3 in known_hosts text file

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

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