Commands by hur1can3 (2)

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Auto Get Missing Launchpad Keys
You can choose these mirror servers to get gpg keys, if the official one ever goes offline keyserver.ubuntu.com pool.sks-keyservers.net subkeys.pgp.net pgp.mit.edu keys.nayr.net keys.gnupg.net wwwkeys.en.pgp.net #(replace with your country code fr, en, de,etc)

history autocompletion with arrow keys
This will enable the possibility to navigate in the history of the command you type with the arrow keys, example "na" and the arrow will give all command starting by na in the history.You can add these lines to your .bashrc (without &&) to use that in your default terminal.

exit without saving history
this exits bash without saving the history. unlike explicitly disabling the history in some way, this works anywhere, and it works if you decide *after* issuing the command you don't want logged, that you don't want it logged ... $$ ( or ${$} ) is the pid of the current bash instance this also works perfectly in shells that don't have $$ if you do something like $ kill -9 `readlink /proc/self`

Split a file one piece at a time, when using the split command isn't an option (not enough disk space)
bs = buffer size (basically defined the size of a "unit" used by count and skip) count = the number of buffers to copy (16m * 32 = 1/2 gig) skip = (32 * 2) we are grabbing piece 3...which means 2 have already been written so skip (2 * count) i will edit this later if i can to make this all more understandable

Blink Caps Lock on HDD activity
Some computers these days don't have an HDD activity light, but they still have a useless caps-lock, so why not re-purpose that light to show HDD activity? Requires setleds and dstat and probably needs to run as root.

Random unsigned integer
works at least in bash. returns integer in range 0-32767. range is not as good, but for lots of cases it's good enough.

Copy a file over SSH without SCP

Shows physically connected drives (SCSI or SATA)
This will show all physically connected SATA (and SCSI) drives on your system. This is particularly useful when troubleshooting hard disks.... or when a mount point seems to be missing.

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)

Mapreduce style processing
parallel can be installed on your central node and can be used to run a command multiple times. In this example, multiple ssh connections are used to run commands. (-j is the number of jobs to run at the same time). The result can then be piped to commands to perform the "reduce" stage. (sort then uniq in this example). This example assumes "keyless ssh login" has been set up between the central node and all machines in the cluster. bashreduce may also do what you want.


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