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I installed my new drive and put Ubuntu server on it. It was working fine except ubuntu server was a bit to raw for me. So, then I decided to go back to my old drive and use the new drive as a second drive (the old OS was still on the old drive). The old ubuntu loads fine but it cannot see the new drive. I have tried putting the second dirve in all the SATA ports I have and I can never seem to see the drive.?

I run the following command to try and reformat it:

fdisk /dev/sdb

and I get the following error:

Unable to open /dev/sdb

I do not have to set any physical pins to let it know it should be the second drive right? Its not like the old IDE days. Is there a certain order to the SATA ports on the board?

Any thoughts on this would be much appreciated...

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What does "fdisk -l" say about what drives are seen in the system? – Kevin Kuphal Aug 19 '09 at 6:06
Thanks for everyones help. You all had really good suggestions and I feal like a complete idiot for what it turned out to be. The power connection on the drive was loose! Once I got power to the drive things became much easier! Imagine that... Anyway I guess on the positive side is that I learned a lot about Linux drives! – stephenmm Aug 24 '09 at 15:55
up vote 2 down vote accepted


fdisk -l

To list all disks and partitions, you could also check the boot log and see if the disk is detected there.

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sudo fdisk -l – Dennis Williamson Aug 19 '09 at 14:29
sudo may have also been the missing piece. – Broam Nov 19 '09 at 17:24

A crude but information rich method of checking for your drive... does going through the kernel output show your drive being listed?

dmesg | less
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There is a certain order to the SATA ports, at least on the boards I've seen so far. The second disk might not show up as /dev/sdb but as /dev/sdc or /dev/sdd if you have 4 ports. But then, there might also be a problem with the disk itself.

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As the previous have posted, you need to make sure you are pointing to the right disk...maybe look at gparted to see if the disk shows up?

this link might help > here <

hope that helps

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Also check out dmesg to see what's happening as the system tries to initialize it. Is it even recognized in BIOS? If you can hot-plug it while the system is running, do tail -f /var/log/messages to see what's happening as you plug it in (then ctrl+C to end).

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I guess by your suggestion that hot-plugging a SATA drive is safe? – stephenmm Aug 19 '09 at 16:20 Basically, your drive controller needs AHCI – churnd Aug 27 '09 at 11:59

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