Commands by opertinicy (3)

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Sysadmin day date of any given year
Calculate the date of Sysadmin day (last Friday of July) of any given year

add static arp entry to default gateway, arp poison protection

Generate random number with shuf
If you don't have seq or shuf, bash can be used.

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

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Monitor open connections for httpd including listen, count and sort it per IP
It's not my code, but I found it useful to know how many open connections per request I have on a machine to debug connections without opening another http connection for it. You can also decide to sort things out differently then the way it appears in here.

list files recursively by size

Run a command only when load average is below a certain threshold
Good for one off jobs that you want to run at a quiet time. The default threshold is a load average of 0.8 but this can be set using atrun.

back up your commandlinefu contributed commands
Use `zless` to read the content of your *rss.gz file: $ zless commandlinefu-contribs-backup-2009-08-10-07.40.39.rss.gz


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