|Summary:||after system restore, could not find filesystem|
|Product:||[Fedora] Fedora||Reporter:||Gene Czarcinski <gczarcinski>|
|Component:||kernel||Assignee:||Kernel Maintainer List <kernel-maint>|
|Status:||CLOSED NOTABUG||QA Contact:||Fedora Extras Quality Assurance <extras-qa>|
|Fixed In Version:||Doc Type:||Bug Fix|
|Doc Text:||Story Points:||---|
|Last Closed:||2008-06-06 18:19:30 UTC||Type:||---|
|oVirt Team:||---||RHEL 7.3 requirements from Atomic Host:|
|Cloudforms Team:||---||Target Upstream Version:|
Description Gene Czarcinski 2008-06-01 23:11:23 UTC
Description of problem: This can be a long story or a short story. Rather than write the "great American novel" I will try to keep this short and just try an provide what I believe are the significant facts. If you need more info as to what/how I did things, just ask. All testing was done in vmware virtuals (guests) and all installs were i386 Fedora 9. I do not believe that vmware is the issue but I can replicate what I did on real hardware ... an old opteron 140. 1. In a vmware virtual (call it f9-t2), do multiple installs of Fedora 9 with grub installed in the partition except for one and use chainloader to boot alternate systems. I am focusing on a Fedora 9 minimal install on sda6 (everything in one partition) and using sda2 as swap ... sda6 is chainloader'ed to boot. 2. To digress for a moment, I am testing a re-write/re-development of partimage called partimage-ng. I used partimage-ng to "full disk" backup everything on f9-t2 and then did "full disk" restores of everything onto a second vmware virtual (call it test8). After restoring, test each system to make sure it worked (they all did). All backups and restores were performed running on the rescue mode of the Fedora 9 network install cdrom. 3. Back to f9-t2 and boot up rescue mode. Mount /dev/sda6 read-only and cd to the mount point. run "dd bs=512 count=1 if=/dev/sda6 of=/root/sda6.mbr" and then scp sda6.mbr over to server storage. Run "dump -0 -f -" and then "tar --xattrs -pzcf -" ... in each case, output is piped to server storage via an ssh tunnel. [I really like the current capabilities of rescue mode] ... after backups, poweroff f9-t2. 4. Move to test8 and bootup in rescue mode. Do "mke2fs -v -j /dev/sda6", mount /dev/sda6 and then cd to the mount point. Input is piped in from server storage via an ssh tunnel. Run "restore rf -" and then "dd bs=512 count=1 of=dev/sda6 if=<xx>" and reboot ... select sda6 for bootup ... booting starts ... and then dies. A Screenshot is attached as being the best way to document the failure. 5. Repeat 4 except use "tar --xattrs -pzxf -" to do the restore ... same failure and I will skip attaching this screenshot. 6. Go back to f9-t2 and update the sda6 system with kernel-220.127.116.11-18.fc9.i686 ... reboot into rescue mode and do dump and tar backups again. No error message from dump or tar. 7. Try the "4 process" (on test8) with the updated kernel ... same failure. Note that during restore, I got a lot of what looked like selinux error messages ... these did not occur the first time. Version-Release number of selected component (if applicable): 1. fresh install of Fedora 9 2. also tried kernel 18.104.22.168-18.fc9 i686 How reproducible: yes
Comment 1 Gene Czarcinski 2008-06-01 23:11:23 UTC
Created attachment 307324 [details] vmware console showing error messages on test8
Comment 2 Gene Czarcinski 2008-06-02 03:45:26 UTC
problem duplicated on real hardware
Comment 3 Chuck Ebbert 2008-06-06 02:04:27 UTC
The UUID changed when you created a new paritition and used mke2fs to create the filesystem...
Comment 4 Gene Czarcinski 2008-06-06 05:46:15 UTC
OK, ... WOW .... and where is this documented? I tried changing /etc/fstab to us the device (dev/sda6) rather than the UUID .... same problem. And what utility can I use to display/change the UUID on a partition?? I know I can fiddle with UUIDs in LVM but how about a regular partition?
Comment 5 Chuck Ebbert 2008-06-06 09:43:03 UTC
(In reply to comment #4) > OK, ... WOW .... and where is this documented? > > I tried changing /etc/fstab to us the device (dev/sda6) rather than the UUID > .... same problem. > > And what utility can I use to display/change the UUID on a partition?? I know I > can fiddle with UUIDs in LVM but how about a regular partition? tune2fs -U
Comment 6 Gene Czarcinski 2008-06-06 18:02:36 UTC
OK, it is kind of hard to argue with success ... I got it to work using tune2fs ... BUT, it would be more than nice if some of this was documented somewhere [if it is, I could not find it] ... and it still leaves the question of some command to DISPLAY the current UUID on a device ... I did find the "findfs" command which will display a device given a UUID but not the reverse of displaying the UUID given a device. I still want to try editing the grub kernel line to say root=/dev/sda6 to see if that would have given me a running system. But, that will not work with "/" on an LVM Logical Volume ... that will need the UUID. With the emphasis that Fedora (and I assume RHEL) is putting on using LVM and UUID, someone knowledgeable of UUID ins-and-outs needs to create some "tips and tricks" on UUID related matters. While I might be able to write something, as I demonstrated, I am not that knowledgeable! Arrgh ... I just did a quick test where I have a minimal install (like on sda6) but this time on a LVM Logical Volume. What I found is that root=UUID= on grub kernel line is different than the LVM Logical Volume's UUID AND you need both ... you still need to do a tune2fs -U on the Logical Volume's ext3 filesystem. I know that you folks at Red Hat are busy and that it is not your (Chuck's) responsibility to get the right documentation written and posted in the appropriate place and/or manual such as for RHEL. So, whose chain do I pull to get some doc out there (besides this BZ report)? Something tells me that this information needs to be available so that someone is not in a panic when they are trying to restore a system from bare-metal. Yes, they can always reinstall but, if someone has taken the time and effort to create real backups, a reinstall does not look appealing.
Comment 7 Gene Czarcinski 2008-06-06 18:19:30 UTC
fedora-documentation docs-request: https://bugzilla.redhat.com/show_bug.cgi?id=450331 closing this as notabug since I consider it to be a lack of documentation rather than a software problem.