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Analyze, check, auto-repair and optimize Mysql Database
A useful way to do a full check and auto repair damaged databases

gzip compression with progress bar and remaining time displayed

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"

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" }

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"

Create a video that is supported by youtube
Takes an mpeg video and coverts it to a youtube compatible flv file. The -r 25 sets the frame rate for PAL, for NTSC use 29.97

Get a list of IP Addresses that have failed to login via SSH
This command shows a sorted list of the IP addresses from which there have been authentication errors via SSH (possible script kiddies trying to gain access to your server), it eliminates duplicates so it's easier to read, but you can remove the "uniq" command at the end, or even do a "uniq -c" to have a count of how many times each IP address shows in the log (the path to the log may vary from system to system)

Convert multiple pdf's to jpg in linux using the convert command

Get your external IP address if your machine has a DNS entry
Easy way to see your real external IP

validate json
I have this saved as jsonlint chmodded +x and file.js is instead $1, but YMMV


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