High Performance Linux Clusters with OSCAR, Rocks, OpenMosix, and MPI [Electronic resources] نسخه متنی

12.3 Notes for OSCAR and Rocks Users

Both OSCAR and Rocks use NFS. Rocks uses
autofs to mount home directories; OSCAR
doesn't. (Automounting and
autofs is discussed briefly in Chapter 4.)

PVFS is available as an add-on package for OSCAR. By default, it
installs across the first eight available nodes using the OSCAR
server as the metadata server and mount point. The OSCAR server is
not configured as an I/O server. OSCAR configures PVFS to start
automatically when the system is rebooted.

With OSCAR, PVFS is installed in the directory
/opt/pvfs, e.g., the libraries are in
/opt/pvfs/lib and the manpages are in
/opt/pvfs/man. The manpages are not placed on
the user's path but can be with the
-M option to man. For example,

[root@amy /]# man -M /opt/pvfs/man/ pvfs_chmod

The PVFS utilities are in /opt/pvfs/bin and the
daemons are in /opt/pvfs/sbin. The mount point
for PVFS is /mnt/pvfs. Everything else is pretty
much where you would expect it to be.

PVFS is fully integrated into Rocks on all nodes. However, you will
need to do several configuration tasks. Basically, this means
following the steps outlined in this chapter. However,
you'll find that some of the steps have been done
for you.

On the meta-server, the directory /pvfs-meta is
already in place; run /usr/bin/mkmgrconf to
create the configuration files. For the I/O servers,
you'll need to create the data directory
/pvfs-data but the configuration file is already
in place. The kernel modules are currently in
/lib/modules/2.4.21-15.EL/fs/ and are preloaded.
You'll need to start the I/O daemon
/usr/sbin/iod, and you'll need
to mount each client using /sbin/mount.pvfs. All
in all it goes quickly. Just be sure to note locations for the
various commands.