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back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

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

Close a hanging ssh session
~ is the ssh control character. If you type it after a newline, you can example force close the ssh session. , ~, then . If you want more info, type ~? when you are connecting using ssh. Very useful to kill of any hanging ssh sessions when nothing else works.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Connect to all running screen instances
There was another line that was dependent on having un-named screen sessions. This just wouldn't do. This one works no matter what the name is. A possible improvement would be removing the perl dependence, but that doesn't effect me.

Bypass with hexencoding, dump /etc/passwd

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" }

Sort file greater than a specified size in human readeable format including their path and typed by color, running from current directory
1. find file greater than 10 MB 2. direct it to xargs 3. xargs pass them as argument to ls

Discover the process start time
That is useful to discover the start time of process older than 1 day. You can also run: $ ls -ld /proc/PID That's returning the creation date of the proc files from the process. Some users reported that this way might show you a wrong date since any other process like cron, for example, could change this date.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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