Commands by cfy (4)

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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

Extract tar.gz file with original permission
-x, --extract, --get extract files from an archive -p, --preserve-permissions, --same-permissions extract information about file permissions (default for superuser) -f, --file=ARCHIVE use archive file or device ARCHIVE -v, --verbose verbosely list files processed

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" }

Find top 10 largest files in /var directory (subdirectories and hidden files included )
Same as above, but modified to show human readable output

Go up multiple levels of directories quickly and easily.
Change to your taste. Much quicker than having to add 'cd' every time. Add it to your .bashrc or .bash_profile.

Discovering all open files/dirs underneath a directory
It may be helpful in case you need to umount a directory and some process is preventing you to do so keeping the folder busy. The lsof may process the +D option slowly and may require a significant amount of memory because it will descend the full dir tree. On the other hand it will neither follow symlinks nor other file systems.

Grab an interface's IP from ifconfig without screen clutter
Sometimes, you don't really care about all the other information that ifconfig spits at you (however useful it may otherwise be). You just want an IP. This strips out all the crap and gives you exactly what you want.

Find the package that installed a command

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

pipe output to notify-send
Route output to notify-send to show nice messages on the desktop, e.g. title and interpreter of the current radio stream


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