Commands by fernandomerces (5)

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Get all ip address for the host

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"

dd if=/dev/null of=/dev/sda
removes all files/filesystems of a harddisk. It removes EVERYTHING of your hard disk. Be carefull when to select a device. It does not prompt for and second check.

Reinstall a Synology NAS without loosing any data from commandline.
Seen many questions how-to reinstall synology nas dsm without loosing data, here you go. Wait for a few min and then head over to http://nasip and setup your fresh installed nas.

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" }

Show some trivia related to the current date
Contrary to logic, typing calendar won't show a calendar, that's the job of cal. Typing calendar will show some trivia related to the current date. Tested against many Linux distros and FreeBSD.

rgrep: recursive grep without .svn
Only excludes .svn from filenames.

Multiplication table
The multiplication table for math study

Delete an IPtable rules based on row number

Join a folder full of split files
If you use newsgroups then you'll have come across split files before. Joining together a whole batch of them can be a pain so this will do the whole folder in one.


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