Commands by elfinkind (1)

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Show a line when a "column" matchs

Find the biggest files
Show the top 10 file size

Query Wikipedia via console over DNS

Remove a line from a file using sed (useful for updating known SSH server keys when they change)
For example, to remove line 5 from foo, type: vi +5d +wq foo

Force machine to reboot no matter what (even if /sbin/shutdown is hanging)
This will cause your machine to INSTANTLY reboot. No un-mounting of drives or anything. Very handy when something has gone horribly wrong with your server in that co-location facility miles away with no remote hands! Suspect this works with all 2.2, 2.4 and 2.6 Linux kernels compiled with magic-syskey-request support.

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" }

Get absolut path to your bash-script
Another way of doing it that's a bit clearer. I'm a fan of readable code.

bulk rename files with sed, one-liner
Far from my favorite, but works in sh and with an old sed that doesn't support '-E'

Creates Solaris alternate boot environment on another zpool.
PS: 'lustatus' gives the list of all alternate boot environments.

Remotely sniff traffic and pass to snort
I have a small embedded linux device that I wanted to use for sniffing my external network, but I didn't want to recompile/cross-compile snort for the embedded platform. So I used tcpdump over ssh to pass all the traffic as pcap data to a "normal" Linux system that then takes the pcap data and passes it to snort for processing.

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