Re: location of home directories
Markus Schabel <markus.schabel <at> tgm.ac.at> writes:
>
> p.carsten <at> arcor.de wrote:
> > Thank you Markus,
> >
> > ok, the part of the skolelinux homedir structure that stuck out to me
> > was the hardcoded "skole" in it.
>
> Yes, i think this is something that isn't really needed, but whoever
> had done this must have some thoughts behind that ;)
In the meantime, probably while beeing asleep, :) I could thought of a
requirement.
Using /skole as a mountpoint for network resouces does not impose any
restrictions in the local use of /home on client workstations.
(Local users etc.)
To keep it more general the mountpoint might be i.e. /net/tjener/home or even
a plain standard compliant /mnt/tjener/home.
>
> > I think skolelinux is already of good
> > use also for non school projects. And a common scheme say at least
> > within Custom Debian Distributions may be desireable.
> >
> > A scheme like
> > tjener.skole.lan:/home/tjener/home0
> >
> > would make it more general and eliminate the need for
> > customizations other than changing hostname and domain.
>
> Yes, that would be good.
>
> > Things I am not yet clear about, and would like to know your thoughs on:
> >
> > -- AFAIK It is currently not possible to do additional mounts to the same
> > mountpoint. So "mount tjener:/home /home" and a subsequent
> > "mount tjener2:/home /home" would only show /home/tjener2/home0 anyway.
>
> Yes, that's correct.
>
> > This means the mounting client machine needs to explicitly mount
> > particular servers to a deeper mountpoint anyway. So the /hostname/
> > part in the directory on the server does not help in keeping mounting
> > volumes from different servers on clients unified.
> >
> > This kind of global namespace mounting is only supported in AFS (AFAIK)
>
> Yes, on servers which need to have all we do the following:
> mount fs01:/home/fs01 /home/fs01
> mount fs02:/home/fs02 /home/fs02
>
> And on computers that only need some of the directories (e.g. the one
> of the currently logged in user) we do the following:
> mount fs??:/home/fs??/markus.schabel /home/fs??/markus.schabel
> (replace ?? with the number of the server the homedirectory of the
> user is physically located)
> > -- I am not sure why to keep different home[0,1,..] volumes around when
> > the servers make use of LVM which allows adding additional volumes
> > transparently later on. (Distinguishing /home/student and
> > /home/teacher might be another thing)
>
> AFAIK it is not possible to use LVM accross different servers. If you
> have a school with some departments (e.g. electronics, information
> technology, ...) and each department has it's own fileserver for the
> student's homedirectories you cannot use LVM but must mount the
> individual home directories of the servers onto one central place (if
> you need them all at one place, e.g. only one external available ftp
> server).
I agree but isn't that what the /fs??/ part from above is for?
When we try distributing volumes to diffenrent locations the perfect solution
would probably be to be able to do this absolutely transparently for users.
I.e the location in the global name space would not need to change.
LVM does abstract from local volumes. But the explicit server source directory
mounts dont allow real abstraction from net locations. With your kind help I
understood that, and why the the /fileserver/ part is necessary.
With explicit mounts there is just no real global namespace support. Wheras
with AFS IIRC you just "mount AFS to /afs" and can then browse
/afs/skole.lan/home/UID and even other domains no matter if the data is
sitting on your department server, anyplace else, or if it is being replicated
on a machine next to yours or even on your own.
I once had an account at a place where they used this Andrew File System I
thought it was realy nice from the user point of view, and feature rich, but I
did not try to install myself yet. Could the afs authentication live
peacefully with skolelinux ldap authentication?
I found a FS comparison I'll post to the "choice of Network FSs" thread.
> > So IMHO at the moment, it might as well be just tjener.skole.lan:/home
> > (or translated into a particular network environment more like:
> > server.city-highschool.lan:/home)
>
> Splitting data across servers may help you a bit if you got one machine
> down, you can use the backup on another server, just add another local
> directory inside /home and change the nfs mounts.
Thank you, now I see the benefits from keeping a /server/ level in place,
(as long as global namespace is lacking ;-)
> Markus
>
Peter
Reply to: