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

Mathias Feiler feiler@uni-hohenheim.de
Tue, 20 Jun 2006 17:35:28 +0200 (MET DST)

Hello ,

If I undersand You the right way .... (long answer)

On Fri, 9 Jun 2006, David Geirsson wrote:

|Hi all,
|I'm preparing to set up OpenAFS for a small network (3-4 users, ~500GB
|of data to store). The server machine has 4x320GB IDE disks in a RAID5
|configuration. There is no backup equipment set up, as this is for a
|personal network and we can't afford it.
|I've read in the AFS docs (which I admit I'm still reading, so this may
|be covered better later) that AFS likes to have its own dedicated
|partitions, and that this is "strongly recommended". I am wondering,
|however, what would happen? Will OpenAFS trample all the files? Because
|the easiest solution for me here would be to let OpenAFS use the data
|partition for its own files,

As long as You use the namei-interface (Linux) ther is a way to mount
/vicep* even if it is not a separate partition. But for now dont ask me for
the -option .

|and then move files from that partition to
|the AFS mount.

Nice idea but not the way AFS is designd.
Imho. the problem steps in on at least two points:

(1) -- Accessmethod to the volumes on a vice partition --
If You are using the origin inode interface to access the /vicep* (as it is
common for Solaris and such) You just cannot move data into the /vicep*
since ther is nothing to move it in. The only thing you see are 76 Byte
files calles Vnnnnnnn.vol (e.g. V1920534048.vol) which represent the
volumeheader. All the other things are hidden in a strange way. Thus You
need a special fsck for such partitions.
If You use namei for the /vicep* there is a directory strukture but the
names are totaly srewd . You wouldn't succseed if You just write in.

(2) --- Access control ---
AFS got acl and volumes. Both of them needs to be represented in the /vice*
While You are thinking of moving files into a vice partition by  unix mv
you probably did not considder volumes (rw,clone,ro,backup) and acl

The proper way is, to have a afs client running on the old fileserver (as
well as  on the AFS server for conveniences) and just copy your data into
the AFS using the afs client.
 	# Create a volume
         vos create afsserver vicepa prj.dump
 	# Mout the volume into the AFS-file tree
	 fs mkm /afs/.mySite/projects/dump prj.dump
	# set the (initial) acl
	 fs sa /afs/.mySite/projects/dump dummy write
 	# Copy the data into the volume
         cp -R /oldDump/* /afs/.mySite/projects/dump
	# Eventually define a clone and/or replicate site of the volume
	 vos addsi afsserver vicepa prj.dump
	 vos addsi afsserver2 a     prj.dump
  	# Eventually do the replication of the volume
	 vos rel  prj.dump

|Anyway, help would be much appreciated.
Well it could be of advantage to join a AFS workshop :

USA / english     :  http://www.central.org/workshop/index.html
Germany / deutsch :  http://www.rz.uni-hohenheim.de/afsws06

This might help to keep You from a few other newcomer-uups as well.

Sincerely , Mathias

|PS: I'm not subscribed to this mailing list. I'll monitor the web
|archive, but it'd be good if I were CC'ed on replies.
|With kind regards,
|David Steinn Geirsson
|Reykjavik, Iceland
|+354 8696608
|OpenAFS-info mailing list

Fuer Rueckfragen  stehe ich gerne zur Verfuegung,  bevorzuge jedoch  tele-
fonische Kontaktaufnahme ( +49 711 459-3949 oder +49 179 6954907 ). Danke.

Hochachtungsvoll und mit freundlichen Gruessen   M.Feiler

Computer: Es gibt nur 10 Arten von Menschen -
solche die es begreifen und dann noch die andern.

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those who understand and those who don't.

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