Commands by sunny256 (3)

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Fill a hard drive with ones - like zero-fill, but the opposite :)
Note: Replace 200000 with drive bytes/512, and /dev/sdx with the destination drive/partition. ;) Note: You may need to install pipebench, this is easy with "sudo apt-get install pipebench" on Ubuntu. The reason I hunted around for the pieces to make up this command is that I wanted to specifically flip all of the bits on a new HDD, before running an Extended SMART Self-Test (actually, the second pass, as I've already done one while factory-zeroed) to ensure there are no physical faults waiting to compromise my valuable data. There were several sites that came up in a Google search which had a zero-fill command with progress indicator, and one or two with a fill-with-ones command, but none that I could find with these two things combined (I had to shuffle around the dd command(s) to get this to happen without wasting speed on an md5sum as well). For reference, these are the other useful-looking commands I found in my search: Zero-fill drive "/dev/sdx", with progress indicator and md5 verification (run sudo fdisk -l to get total disk bytes, then divide by 512 and enter the resulting value into this command for a full wipe) $ dd if=/dev/zero bs=512 count= | pipebench | sudo tee /dev/sdx | md5sum And this command for creating a file filled with ones is my other main source (besides the above command and man pages, that is - I may be a Linux newbie but I do read!): $ tr '\000' '\377' < /dev/zero | dd of=allones bs=1024 count=2k Hope someone finds this useful! :) Cheers, - Gliktch

List top 20 IP from which TCP connection is in SYN_RECV state
List top 20 IP from which TCP connection is in SYN_RECV state. Useful on web servers to detect a syn flood attack. Replace SYN_ with ESTA to find established connections

Regenerate the /etc/mtab file

Reverse SSHfs mount,
While `sshfs $REMOTE_HOST:$REMOTE_PATH $LOCAL_PATH` "pulls" a directory from the remote server to the local host, the above command does the reverse and "pushes" a directory from the local host to the remote server. This makes use of the "slave" option of sshfs which instructs it to communicate over plain stdin/stdout and the `dpipe` tool from vde2 to connect the sftp-server stdout to the sshfs stdin and vice-versa.

reclaim your window titlebars (in ubuntu lucid)

Which fonts are installed?
See all fonts installed in your system

Scans for open ports using telnet

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

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

Force wrap all text to 80 columns in Vim
This is assuming that you're editing some file that has not been wrapped at 80 columns, and you want it to be wrapped. While in Vim, enter ex mode, and set the textwidth to 80 columns: $ :set textwidth=80 Then, press: $ gg to get to the top of the file, and: $ gqG to wrap every line from the top to the bottom of the file at 80 characters. Of course, this will lose any indentation blocks you've setup if typing up some source code, or doing type setting. You can make modifications to this command as needed, as 'gq' is the formatting command you want, then you could send the formatting to a specific line in the file, rather than to the end of the file. $ gq49G Will apply the format from your current cursor location to the 49th row. And so on.


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