Commands by dan (5)

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Send a backup job to a remote tape drive on another machine over SSH
I use this all the time for taking manual backups of stuff i want to keep but not important enough to backup regularly.

Check a nfs mountpoint and force a remount if it does not reply after a given timeout.
Based on the execute with timeout command in this site. A more complex script: #!/bin/sh # This script will check the avaliability of a list of NFS mount point, # forcing a remount of those that do not respond in 5 seconds. # # It basically does this: # NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH) # TIMEOUT=5 SCRIPT_NAME=$(basename $0) for i in $@; do echo "Checking $i..." if ! perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $i" > /dev/null 2>&1; then echo "$SCRIPT_NAME: $i is failing with retcode $?."1>&2 echo "$SCRIPT_NAME: Submmiting umount -fl $i" 1>&2 umount -fl $i; echo "$SCRIPT_NAME: Submmiting mount $i" 1>&2 mount $i; fi done

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

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

get time in other timezones
On Ubuntu, if tzwatch is installed, then you can call up in terminal the output for every time zone configured in gWorldClock.

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" }

Clear the terminal screen

Selecting a random file/folder of a folder
Also looks in subfolders

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

Fix VirtualBox error


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