Raid Analysis
Download the text file “raid analysis.txt” its below and download notepad++ and view the text file with notepad++, as it has a great feature of zooming out with the control key + mouse wheel. IF you want to follow along with your linux box, dont ssh via putty, use cygwin as you can zoom out with the control key and the mouse wheel.
This is my experiment on making 4 small disks (2 mb each or so) and making a raid out of it, then putting it into a logical volume and making a filesystem on it, and mounting it and writing a small file to it… Meanwhile our eyes are set on a side by side view of all the data (the first provided script called c.sh is a terrible script that just has a verticle look to it, so skip that part, then the b.sh is a mediocare script, the best side by side script is with a.sh which shows you a hex view of all the data, you can edit the a.sh to show you other stuff in “od -Ad -c” change it to “od -Ad -a” or “od -Ad -x”, where c is ascii, so is a but just a slightly different view, x is pure hex, -Ad for the curious make the sidebar that tells you @ what byte you are in decimal instead of hex. I dont know about you but understand locations better in decimal then hex.)
I think the meaty part of the article actually comes above in the middle right when all the scripts are introduced… not to be confusing but when i started writing this script i called the crap script the a.sh script because it was my first script, i change it later on to c.sh script to represent that its not the better script
This paper is not really formated for publication, like none of my stuff is, its more of personal notes and if you understand them then awesome..
I think this one of my better works because if you learn what this shows you, you do really get a much better understanding of raids, lvm, etc.. and all the superblocks and the locations…
NOTE: to make this better instead of looking byte by byte instead represent a MB or a certain amount of blocks with a a character (if any byte is changed in the MB or block size unit, then mark the byte corresponsing to it as changed – like a bitmap)
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