View Full Version : mount: cannot find "dev/root"
16th February 2009, 11:48 PM
My new install of Fedora 11 Alpha hangs very early with the message
mount: cannot find "dev/root"
this looks like perhaps a new old problem. There are some threads talking about older versions with such a problem. Has anyone else encountered it with 11 Alpha? Suggestions on what to try would be greatly appreciated.
17th February 2009, 12:07 AM
If it's a SCSI drive see the suggestion in the sticky in general support, common problems and their workarounds. If it's not a SCSI drive, I don't know. One possibility--did you use ext4 as the file system and not make a separate /boot partition?
17th February 2009, 04:29 AM
I've had no problems with Fedora 8, 9 or 10. This is new. I'll get back to you on the SCSI drive thing. The computer is a double drive notebook AmilioXi25550 from Fujitsu Siemens.
17th February 2009, 04:37 AM
Chances are it's not a SCSI then.
My other guess is as mentioned, that perhaps it's ext4 without a separate boot partition. Hrrm, no, that can't be right either, because if you don't create a separate /boot during installation, it will give you an error message if you're using ext4.
17th February 2009, 04:48 AM
In Anaconda I simply removed the check from my windows drive and let fedora do it's thing with the second drive (default).
I am in Germany and must drive to work now so I'll be back later.
18th February 2009, 03:42 AM
I had this problem on a laptop. I tried the install using drive encryption first and got the error. So I figured I would try a reinstall without encryption. Same problem. After one more install with drive encryption back and still having the problem, I booted with a rescue cd and found that the root mount point in grub.conf references the UUID of the logical volume created during install. The problem that I had was the it was the wrong UUID. It had a completely different UUID when I used lvdisplay. After correcting the UUID problem Fedora Alpha x86_64 bit booted just fine.
18th February 2009, 09:08 PM
we are on the right track, I think.
When the system starts to boot it gives the name of the lvm logical drive. The UUID in grub.conf was not the same as what lvdisplay gave me. I changed the grub.conf to suit the UUID. The system still does not boot and the error message is the same.
I looked in the fstab and found that fedora now uses UUIDS for /, /boot and swap entries. The UUID that is reported to fail is the entry that is written for the swap. I tried the command lvdisplay -v swap which did not work.
Do I need to use UUIDs in the fstab? Now could I check for the correct value for the swap or should they all be the same as the main LVM.
The fstab lists these three entries as ext3. I think anaconda sets up /boot as ext3 and the main LVM is now ext4 in Fedora 11 ALPHA. What should I try next?
19th February 2009, 02:20 AM
Looking back at my F11 machine I see that I used the volume group name in grub.conf not the UUID. I don't remember if I tried UUIDs or not. But with the path to the volume group listed in grub.conf (/dev/vgname/lvname) all boots well. Also I looked at my fstab and the root entry (/) is the volume group name not a UUID and the type is ext4. My fstab does use a UUID for /boot with a type of ext3. The swap entry is a volume group name. I did not modify any of these entries to get the system to boot. The changes to grub.conf was enough to get the machine to boot.
21st February 2009, 04:19 PM
I have this problem too. I checked my grub partition entries and they appeared to be ok. I have an ext3 boot partition and an ext4 /. I upgraded to 11 from 10 with rawhide. Once I upgraded to 11 I could boot ok with the old Fedora 10 kernel, but when I booted the new 29 kernel I kept getting this same error.
22nd February 2009, 12:39 AM
I read several forums and tried in grub.conf to change the UUID to the value of what lvdisplay gives. It didn't work. In one of the bug reports they suggest something with root=/dev/VolGroup00/Fedorall or so.
When I returned to my grub.conf I read the comment header.
# grub.conf generated by anaconda
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd1,0)
# kernel /vmlinuz-version ro root=/dev/VolGroup00/LogVol00
# initrd /initrd-version.img
I thought if anaconda had written it why not try it. With the entry for my root value set as shown in the header my system is up and running:)
It is written that this problem originates with version of one of the initrd files that ends with 75 in the version number. You should update this file and regenerate the initrd. It remains a mystery to me where I would have found the new file. The Bug reports can be found at:
Years ago when I was trying out distros Ubuntu had a similar problem with UUIDs. Will Fedora be using this method in the future? Does the use of UUIDs have advantages? If there are only minimal advantages can I replace the entries in the fstab file with /dev/VolGroup00/fedora11 and get rid of them there as well?
22nd February 2009, 12:58 AM
The advantage might be if you have multiple disks and for whatever reason on different installs device names change (sda becoming sdb). (Or of course, if adding a disk.)
I've had no trouble with single boot installations--where I've had minor problems is when running some multiboot installs and the swap space is given a different UUID by each installation. :) In that case, I simply change it /dev/sda2 or whatever it is in each install's fstab.
I actually haven't tried editing the grub line but I would assume if you edited both the line in grub and your /etc/fstab it would be alright to change both to, for example, /dev/sda1. (However, as I said, I haven't tried that and if it breaks something don't blame me.) :)
Whether it's actually The Next Great Idea (TM) or a solution in search of a problem, I don't know. So long as it only causes me minor inconvenience, I don't worry about it. It seems as if it is The Wave of the Future. <shrug>.
22nd February 2009, 01:37 AM
Because of my work I must use Microsoft products so I am using a notebook with 2 250G hard-drives. For the most part Fedora (anaconda) has been the best installer I have used. Let's hope in the future it remains so.;)
Thanks for your help.
22nd February 2009, 01:46 AM
Well, I have no idea if I helped, but you're more than welcome.
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