Re: [gentoo-user] Extended file attributes: ext4

Canek Peláez Valdés <caneko@×××××.com> [12-04-08 20:28]:
> On Sun, Apr 8, 2012 at 11:44 AM,  <meino.cramer@×××.de> wrote:
> > Mick <michaelkintzios@×××××.com> [12-04-08 18:40]:
> >> On Sunday 08 Apr 2012 16:56:23 David W Noon wrote:
> >> > On Sun, 8 Apr 2012 17:26:03 +0200, meino.cramer@×××.de wrote about
> >> >
> >> > [gentoo-user] Extended file attributes: ext4:
> >> > > is it possible to go from an ext4-filesystem with no extended file
> >> > > attributes to one with extended file attributes without reformatting
> >> > > the disk or other very risky low level things just by adding this
> >> > > feature to the kenrel (?) ?
> >> >
> >> > Yes, it's simple.
> >> >
> >> > You need to ensure that your kernel configuration has the extended
> >> > attribute support (ACL is a good idea too) and you have booted with the
> >> > ext4 driver so configured.
> >> >
> >> > You then add the xattr option in /etc/fstab for the filesystem(s) where
> >> > you want extended attribute support.  If you do that before you reboot
> >> > (as above) then you will have full extended attribute support.
> >>
> >> I thought that you are meant to pass such options on the CLI at the time you
> >> are formatting the partition ... is this incorrect?
> >>
> >> Of course if you must format the drive with such options then the data won't
> >> survive.
> >> --
> >> Regards,
> >> Mick
> >
> >
> > Hi,
> >
> > thank you very much for all the input.
> >
> > To clearify things a little:
> >
> > Status quo: System with ext4 and no extended attributes.
> > Where I want to be: The same system with extended attributes.
> >
> > Way to go: No reformatting and mkfs and all that things. Only kernel
> > reconfiguring / recompiling / rebooting and emerging some tools.
> >
> > Possible?
>
> As others had said, this is possible. I used this guide:
>
> http://www.debian-administration.org/articles/643
>
> You need basically to enable the ext4-only features:
>
> tune2fs -O extents,uninit_bg,dir_index <partition>
>
> Do the fsck:
>
> fsck.ext4 -yfD <partition>
>
> And (optionally) convert all the files and directories to use extends:
>
> find <directory> -xdev -type f -print0 | xargs -0 chattr +e
> find <directory> -xdev -type d -print0 | xargs -0 chattr +e
>
> I did this on my laptop and desktop (including the root filesystem,
> booting into emergency mode with systemd), and everything worked
> perfectly.
>
> Note, however, that you *need* GRUB2 if your kernel lives in an ext4
> partition that it's not longer compatible with ext3. Don't do the
> change without migrating to GRUB2 before.
>
> Regards.
> --
> Canek Peláez Valdés
> Posgrado en Ciencia e Ingeniería de la Computación
> Universidad Nacional Autónoma de México
>

Ok, thanks for the introduction and the link, Canek! :)

Best regards,
mcc