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video volume boost

Port Knocking!
Knock on ports to open a port to a service (ssh for example) and knock again to close the port. You have to install knockd. See example config file below. [options] logfile = /var/log/knockd.log [openSSH] sequence = 3000,4000,5000 seq_timeout = 5 command = /sbin/iptables -A INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn [closeSSH] sequence = 5000,4000,3000 seq_timeout = 5 command = /sbin/iptables -D INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn

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"

Make a playlistfile for mpg321 or other CLI player
A short variant if you have only one directory whit only audio files in it.

get all Google ipv4/6 subnets for a iptables firewall for example (updated version)
google has added 2 more netblocks...

reapair all mySQL/mariaDB databases
while dumping database if you see following error/warning than you have to repair broken tables/rows

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" }

Watch Network Service Activity in Real-time

Cancel all aptitude scheduled actions
Very handy if you have done a package selection mistake in aptitude. Note that it's better to do a Ctrl+U (undo) in aptitude if possible, because the keep-all will clear some package states (like the 'hold' state).

Clear filesystem memory cache
Found here: http://ubuntuforums.org/showthread.php?t=589975


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