Re: Dump/Restore Errors

[Dr J Austin]

> On Wed, 3 Mar 2010, John Austin wrote:
> > Date: Wed, 03 Mar 2010 13:06:11 +0000
> > From: John Austin 
> > Reply-To: [e-mail],
> >     Community support for Fedora users 
> > To: [e-mail]
> > Subject: Dump/Restore Errors
> >
> > Hi
> >
> > I have been following recent threads about the best way to clone/backup
> > disks.
> >
> > "Risks of backing up live mounted filesystems using dump(8)"
> >
> > I have just tested dump/restore using a System Rescue CD
> > using dump 0.4b42
> >
> > The source /dev/sda7 is a fully working updated F12 / partition
> > (including /boot)
> >
> > The destination is a similar partition on the same disk /dev/sda9
> >
> > mkfs -t ext3 /dev/sda9
> > mkdir /mnt/out
> > mount /dev/sda9 /mnt/out
> > dump 0f - /dev/sda7 | (cd /mnt/out; restore -rf -)
> > 40GB dump/restore took 46 minutes
> >
> > I received 9 errors of the type
> >
> > resync restore, skipped 1 blocks
> > error in EA block 1
> > magic = 0
> >
> > Google tells me that dump saves as is
> > and that restore is finding an error in an Attribute Block
> > (maybe/sometimes associated with NFS)
> >
> > I have not been able to find definitive answers to some obvious
> > questions.
> > Are these fatal for the file concerned hence invalidating the clone/backup?
> >
> > I am unsure how to interpret the error message
> >
> > Why are they present in the first place?
> >
> > How can I find which files they are caused by?
> >
> > Can I correct the errors, do I need to?
> >
> > Grateful for any help
> >
> > Regards
> > John
> On Wed, 2010-03-03 at 18:56 -0600, Paul Thompson wrote:
> I believe these generally fall on files which were deleted between when 
> the index was created and the file is reached in the backup.

Second attempt at posting !!

Hi Paul

Yes I had thought along those lines as I originally
had the source partition mounted.

However I repeated the dump/restore and the case shown above was
with the source unmounted and hence I believe the errors are
present in the source partition/file system.

I assume something is wrong in the SElinux extended attributes?

I have seen this suggestion for "processing" the source file system
before executing the dump/restore.

However I don't know enough about SELinux to feel confident about using it.

Disable selinux; reboot and then 
find . -exec setfattr -h -x security.selinux '{}' ;

Is it a good idea to zap all SELinux attributes in the first place?
a. When the partition/file system is / for the operating system
b. When the partition/file system is mounted from a rescue CD boot?

John