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diff --git a/src/Duplicating_a_USB_Stick_with_dd.ascii b/src/Duplicating_a_USB_Stick_with_dd.ascii deleted file mode 100644 index 6f61874..0000000 --- a/src/Duplicating_a_USB_Stick_with_dd.ascii +++ /dev/null @@ -1,79 +0,0 @@ -Duplicating a USB Stick with dd -=============================== -:author: Aaron Ball -:email: nullspoon@iohq.net - - -== {doctitle} - -I have a USB stick that I use for fixing friends computers (among other things) -that runs Arch Linux. It seems that their most frequent problems are either -crashed hard drives or a virus that makes their computer unusable. The quick -solution to backing their data up in either case is to boot an external drive -and use that OS to copy the data off their drive (assuming you can still get to -it that is). Unfortunately, flash memory has a maximum number of times that you -can write to it, which I hit a bit quicker than I'd like running an operating -system off of a USB stick. As you likely guessed, my USB stick is failing -(remarkably I've been using it to do this for several years). - -Last night whilst (oh yes, whilst) brushing my teeth, I had an epiphany. I -realized that instead of re-installing Linux on a new USB stick, I could use dd -to duplicate one USB stick onto another. I tried it, and sure enough, it works -almost perfectly. I say almost because there was one minor problem that I will -get to in a minute. Firstly though... The command *dd* is used for making -bit-for-bit duplicates or data. In this case, we're duplicating the exact bits -on one device (a USB stick) to another device (another USB stick). You can -actually use dd to duplicate most Linux ISO installation files onto a USB stick -as well. It works very similarly to burning a CD. Now that that's explained, -here's the command I used. - -Assuming my source USB stick is at /dev/sdb and my destination stick is at -/dev/sdc (partitions don't matter here because we're duplication the entire -drive, not just one partition). - ----- -dd if=/dev/sda of=/dev/sdb ----- - -(The *if* is the "input file" and *of* is the "output file") That will likely -take a while. For me it ran at 2.3 megabytes per second. Yours might run a bit -slower as my destination USB stick has an average write speed of 25 MBps which -is a bit higher than typical USB sticks (many thanks to Newegg for the great -price). On the flip side, my source usb stick was starting to fail, so it might -go way faster. I'm not really sure. - -Okay, now that one issue I had. - -Two different 8 gigabyte USB sticks (that's what I used) are likely not going -to have the exact same amount of space on them. If your destination USB stick -is even slightly smaller than your source disk, you'll miss some data due to -the disk being full (in the case of dd, even empty space has bits in it that -get transferred). This will cause problems for you because the filesystem will -say that it starts here and ends there, when the actual partition ends earlier -than expected. While this likely won't cause issues for you other than your -machine complaining about it, it could result in some data loss. Either way, -the way we get around this issue is really simple. Once you've duplicated your -USB stick and booted the new one, you should see the following error: - ----- -The filesystem size (according to the superblock) is derpderpderp blocks The -physical size of the device is blerdibler blocks -Either the superblock or the partition table is likely to be corrupt! ----- - -Just run this command and it should solve your issue - ----- -resize2fs /dev/sd-lastpartition ----- - -In my case that command was *resize2fs -/dev/sdb4* (my /home partition). - -May there be utility USB sticks for all! - - -Category:Linux - - -// vim: set syntax=asciidoc: |