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display systemd log entries for sshd using "no-pager" (a bit like in pre-systemd: grep sshd /var/log/messages)
In pre-systemd systems, something like: "# grep sshd /var/log/messages" would display log events in /var/log/messages containing "sshd". # journalctl -u sshd --no-pager The above command displays similar results for systemd systems. (Note that this needs to be run with root permissions to access the log data.)

Stop Flash from tracking everything you do.
Brute force way to block all LSO cookies on a Linux system with the non-free Flash browser plugin. Works just fine for my needs. Enjoy.

Open the current project on Github by typing gh
Written for Mac OSX. When you are working in a project and want to open it on Github.com, just type "gh" and your default browser will open with the repo you are in. Works for submodules, and repo's that you don't own. You'll need to copy / paste this command into a gh.sh file, then create an alias in your bash or zsh profile to the gh.sh script. Detailed instructions here if you still need help: http://gist.github.com/1917716

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

Identify differences between directories (possibly on different servers)
This can be much faster than downloading one or both trees to a common servers and comparing the files there. After, only those files could be copied down for deeper comparison if needed.

Backup files incremental with rsync to a NTFS-Partition
This will backup the _contents_ of /media/SOURCE to /media/TARGET where TARGET is formatted with ntfs. The --modify-window lets rsync ignore the less accurate timestamps of NTFS.

clean up memory of unnecessary things (Kernerl 2.6.16 or newer)
run sync first to flush useful things out to disk!!! To free pagecache: echo 1 > /proc/sys/vm/drop_caches To free dentries and inodes: echo 2 > /proc/sys/vm/drop_caches To free pagecache, dentries and inodes: echo 3 > /proc/sys/vm/drop_caches

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" }

Reinstall Grub

Change active bond slave
This forces a bonded interface to switch to another slave in the bond as its active slave.


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