Hi Franco--
Franco Broi wrote:>
> Does the MDS have to be connected to the same network media as the
> storage servers and clients?
No, it does not.
> For the MDS I''m thinking that I need 2 machines, both connected to
a
> dual ported RAID array for failover, but it would be a shame if I have
> to buy 2 IB HBA''s and use up IB 2 switch ports for what
I''d imagine to
> be a relatively small amount of network traffic.
>
> If the IB switch supports IB to Ethernet bridging, could these machines
> be connected via Ethernet?
Some of our production installations already use a mix of different
networking types (Elan and TCP), with Portals routers. It is even
better if the network fabric takes care of the routing/bridging for us,
and we don''t have to do anything special.
> My current setup has a 1GB MDS, does the number in
> /proc/fs/lustre/mds/echo5-mds/filestotal (230880) indicate the number of
> files I can have on the luster filesytem irrespective of filesystem
> size? We have a relatively small number of large files so does this mean
> I can get away with a small amount of MDS storage?
That number is the count of free inodes on the MDS. It is just one of
possibly many limiting factors, such as free disk blocks, and free
inodes on the OSTs.
However, what you say is accurate. The MDS only stores a small amount
of metadata per file, along with the directory layout. If you only have
a small number of files, regardless of their size, then you can get away
with less MDS storage.
Thanks--
-Phil