[OpenAFS] How does AFS deal with non-AFS files on its partitions?

Derek Atkins warlord@MIT.EDU
Wed, 28 Jun 2006 11:10:42 -0400


"Dav=C3=AD=C3=B0 Geirsson" <davidgeirs@gmail.com> writes:

[snip]
> Hi Mathias, thanks for your reply.
>
> I think you misunderstand my problem (I probably wasn't very clear in
> my original mail)
>
> The problem is that I need to get the files onto the AFS mount once
> I've created it. At the moment they are on a single linux ext3
> filesystem:
>
> /dev/md0              881G  532G  349G  61% /data
>
> /dev/md0 being the RAID5 array.

AFS needs to use /vicepa, but /vicepa does not need to be a mount point.
Indeed, it can be a symlink, so long as you're using the NameI fileserver
(e.g. on Linux).

ln -s /data /vicepa
touch /vicepa/AlwaysAttach
[ start AFS Servers ; start AFS Client ]

> I want to set this array up as an AFS partition at /vicepa, but I have
> nowhere to store the data while I set up AFS. I want to merge this
> data into the AFS tree once it is operational. I was wondering what
> would happen if I simply mounted the current filesystem, with the
> files and directories currently on there. I realise that AFS wouldn't
> recognise the files, and I couldn't use them on the AFS, but if they
> are left alone, I can then move those files from /vicepa to the /afs
> mount one file tree at a time, making them part of the AFS tree, all
> the while without disturbing the filesystem already there.

This works just fine...  With one caveat (see below).

> I hope this made more sense than my previous post. Thanks for the
> pointer to the workshops, I'd love to go. I doubt my finances will
> allow me to attend this year unfortunately, but you never know.

Are you planning to "mv" or "cp" the data?  If you're planning to "cp"
the data you'll need more disk space, because you've only got 39% of
the partition free, so you couldn't easily duplcate the full data set
into AFS.  However if you plan to 'mv' the data then as you move it
from the ext3 into AFS it will just get transfered from the direct
ext3 data to the indirect AFS data.

-derek

--=20
       Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
       Member, MIT Student Information Processing Board  (SIPB)
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