[Samba] Ideas for distributed Samba servers

[Ravi Channavajhala]

On Sun, Apr 11, 2010 at 8:14 PM, Adam Tauno Williams
<awilliam at whitemice.org> wrote:
> On Sat, 2010-04-10 at 10:14 -0700, Eric Shubert wrote:
>> Robert LeBlanc wrote:
>> > I'm trying to think about how to setup a Samba system and would like to pick
>> > the brains of some experts. We are looking up put a large amount of storage
>> > ~75TB in a central data center. We have some remote (ok, not remote, but
>> > across slower links, ok if you consider several hundred clients over 1Gb to
>> > be slow) locations that we would like to set up samba servers that 'cache'
>> > the file system and serve it up to the clients in the building and sync with
>> > the main data center storage.
>
> a.) I don't think you can really do that with a 'file server'
>
> b.) I believe what you describe is almost exactly how AFS works.
> <http://www.openafs.org/>
>  "OpenAFS is the world's foremost location independent file system."
>
> c.) Most SAN vendors provide a block-level replication solution for
> their products.
>
>>  The idea is have a couple of TB that are
>> > located in the building that serve up the Samba share. When a client
>> > requests a file, if it's in the local cache it is served up from there, if
>> > not then the Samba server grabs the file from the main data center and
>> > serves it to the client. When a file is written, something like rsync is
>> > used to transfer only difference back to the main data center. The problem
>> > is that I'm not sure of a file system that does this. We are using Lustre on
>> > our HPC, but this won't do what we want.
>
> With all the fun of file locking, concurrent access, etc... I think what
> you describe just won't work, or at least will never work well.  Why not
> just you a groupware server that supports document check-out and
> check-in;  that seems like the correct solution to me.   Or possibly
> something like iFolder <http://ifolder.com/ifolder>


WAFS (Wide Area File System) appliances can be very well deployed for this
sort of thing precisely.  Unfortunately, I don't know of any opensource
project for WAFS.  However, commercial solutions such as Riverbed, Expand
Networks, CISCO/WAFS, Juniper/Peribit do exist.

Regards,
/rkc

CTO
DCiEra (P) Ltd