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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" }

tcmdump check ping
capture only ping echo requests with tcpdump

Produce a pseudo random password with given length in base 64

currently mounted filesystems in nice layout
Particularly useful if you're mounting different drives, using the following command will allow you to see all the filesystems currently mounted on your computer and their respective specs with the added benefit of nice formatting.

Convert IP octets to HEX with no dots.
Converts IP octets to hex using printf command. Useful for generating pxeboot aliases in the pxelinux.cfg folder.

Force an fsck on reboot
Force an fsck on reboot. Useful on a system where / has mounted read-only because of file system issues.

Rip a CD/DVD to ISO format.
An easy method to generate ISOs from CD/DVD media.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Get your commandlinefu points (upvotes - downvotes)
Like command #4845, prints score, number of entries, and average score.

Add the time to BASH prompt
Adds the time in 12hr AM/PM format to the beginning of a prompt. Change \@ to \t for 24-hour time or \T for 12hr without AM/PM. To keep the time the next time you open a terminal, edit ~/.bashrc and stick the command at the bottom.

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