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I'm confused-- I booted from a ubuntu cd and selected the "try ubuntu" option. As I understand it, this is the new "live cd" style.

I then try to check my HDD using fsck and it says that /dev/sda is in use.

I think, ok, well let's unmount it and issue umount /dev/sda/ -- and it says /dev/sda is not mounted.

What's up with that? I thought that if the disk was unmounted then how could it be in use? Why can't I check it?


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closed as off-topic by psusi, Braiam, Eric Carvalho, BuZZ-dEE, Avinash Raj Mar 26 '14 at 10:26

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This describes a problem that can't be reproduced that seemingly went away on its own or was only relevant to a very specific period of time. It's off-topic as it's unlikely to help future readers." – Braiam, Eric Carvalho, BuZZ-dEE, Avinash Raj
If this question can be reworded to fit the rules in the help center, please edit the question.

Weirder-- now able to run badblocks-- and it throws an error (still under liveCD) that the computer has 0 disk remaining. –  user101289 Jan 10 '13 at 1:09
This question appears to be off-topic because it is about a simple typeo. –  psusi Mar 24 '14 at 3:31

2 Answers 2

/dev/sda is the whole disk. Disks are divided into partitions. One of the partitions may contain a filesystem you can fsck, such as /dev/sda1. You don't fsck the whole drive.

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this drive is not partitioned. It's basically a blank disk –  user101289 Jan 10 '13 at 1:22
@user101289, then there would be nothing there to fsck. Most likely it is not blank. What does sudo fdisk -lu /dev/sda show? –  psusi Jan 10 '13 at 1:23
there's no output from sudo fdisk -lu /dev/sda either. This despite the fact that I'm currently running badblocks /dev/sda right now. –  user101289 Jan 10 '13 at 1:31
@user101289, what do you mean no output? It has to say something –  psusi Jan 10 '13 at 1:34
nope. ubuntu@ubuntu:~$ sudo fdisk -l ubuntu@ubuntu:~$ –  user101289 Jan 10 '13 at 1:37

You can still use a disk even if it's not in use.

Since almost everything is a treated as a file in Linux, you could access /dev/sda without mounting it. You could even write data to it (which would be a bad idea as it would overwrite what's there).

Where you doing anything that may have used the disk? Did you run any potentially malicious commands, or follow any advice (especially online advice) that, in hindsight, seems a bit sketchy? How much space did you have to begin with?

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No, I haven't tried anything except the badblocks (and the fsck, that failed). The drive should have about 350GB, and as far as I know there's nothing on it-- so I'm not sure how or why it'd say it's out of space. –  user101289 Jan 10 '13 at 1:23
@user101289 Perhaps /dev/sda is not your hard drive? What do you get from "sudo fdisk -l" ? –  Vreality Jan 10 '13 at 1:27
absolutely nothing-- there's no output at all! –  user101289 Jan 10 '13 at 1:30

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