Re: [K12OSN] NFS and Samba questions

[<jeffr odeon net>]

I believe that you will run into major problems with soemthing like this,
mainly because (IIRC) you can't NFS mount data from a storage box onto
your server and then re-share that NFS mounted filesystem via NFS to
another system.  You may be able to get away with it via Samba, but I
rather doubt it.

A distributed filesystem like AFS, Coda, or GFS (and there are others) may
work better, but if you need to share that distributed filesystem to other
boxes via NFS or Samba you may still have problems.  For example, I know
GFS (and presumably OpenGFS) still has some major issues with file locking
if you try to re-share a GFS filesystem to other systems via NFS.

About the only way I can think of to do this is with the network block
device (http://nbd.sourceforge.net/).  NBD will let you mount a raw
partition from one system as a pseudo local partition which you can put
the filesystem of your choice on.

Be careful though, I wouldn't try to connect the storage nodes to the
server over any sort of WAN link - well, ATM, or a large optical pipe
might work (watchout for road crews with backhoes though), but if you can
afford that you could also afford a netapp F800 Filer.  Anyway, I'd
probably put together several identical storage boxes, put them on their
own network behind the server, and do a software raid of the mounted space
on the main server so that you can handle a storage box failing.  You can
scale to very large amounts of storage that can be shared via NFS or Samba
(or both) this way.  I think linux currently (assuming a 2.4.x kernel) has
a max filesystem size of 2 terabytes, if you need more then mount multiple
file systems on the server.

Realistically though, you can get an 8-port 3ware ide raid card
(www.3ware.com) and x8 160 gig Maxtor drives to get over a terabyte of
storage right on the server which would have less hassle, probably less
cost, and less likely to fail if someone pulls the wrong ethernet cables.

www.pricewatch.com is a good starting point for finding hardware prices,
and IIRC they have a vendor listing the 3ware Escalade 7850 ide raid
controller for right around $550.  It works just fine with linux (I'm
using a 4-port card in a redhat 7.1 box and have been quite happy with
it).  Choosing the right case takes some care though, as ide cables
lengths are much shorter than SCSI (typically 18 inches to conform with
the EIDE specs, but you can get longer cables, I've had success with up to
24 inch cables).

Jeff


On Tue, 26 Mar 2002, Quentin Hartman wrote:

> Greetings-
> 	I am thinking about using multiple NFS servers, with filesystems mounted
> on one central Samba / NFS server ( effectively making the setup similar to
> Microsoft's DFS for NT) so that all my staff and students can access their
> work from both the Linux terminals I have going (great work guys!) and the
> Win 9x workstations throughout the District. My biggest concern is the
> performance of the Samba machine. How beefy of a machine am I going to need
> to act as the "hub" for this layout? I expect to have no more than 300
> simultaneous requests to it, and that is fine, that hardware shouldn't have
> a problem with that, but how does adding NFS to the mix impact things? I
> have not used NFS before and not found anything online that seems to refer
> to using NFS and Samba together this way to achieve a multi-platform
> approximation of DFS. Any thoughts?
>
> -Regards-
>
> -Quentin Hartman-
>
>
>
> _______________________________________________
> K12OSN mailing list
> K12OSN redhat com
> https://listman.redhat.com/mailman/listinfo/k12osn
> For more info see <http://www.k12os.org>
>
>