Access, usage, and filesystem layout on the PPPL cluster

1. The PPPL cluster is only accessible from within the PPPL network.
2. All hosts, except for portal, are no-login machines, reserved for batch job processing. You cannot 'ssh' to any individual host from outside the cluster.
   
3. You can 'ssh' to portal.pppl.gov and be placed onto a host in a small pool of interactive hosts. From there, you can view files resident on batch-only hosts (see filesystem information below).
4. telnet and rsh are disabled.
5. ftp into any cluster node is disabled -- use scp.
6. ftp from  cluster nodes is enabled.

1. The UNIX cluster /u, /p, and /l filesystems are mounted on each host of the cluster and have read and write access.
2. The host portal.pppl.gov has mounted every /local filesystem from every batch-only host in the cluster. The path is /l/<node>. For example, to see the files of the /local filesystem on kestrel 072, you would go to the directory /l/kestrel072. To see the files of the /local filesystem on sunfire03, you would go to the directory /l/sunfire03.
3. All remote filesystems are mounted using the automounter facility. Thus, the filesystem only becomes available when a user 'cd's into a directory. For example, if you 'cd' to /p, you might see only a few directories, but if you then 'cd' to the directory you want to access, it will be automatically mounted for you.