Good news for all those of you who have access to a Cray T3E parallel
computer:
Even if no AFS client exists for this architecture we could allow our
users to store and retrieve data from AFS by some extensions to the 'fs'
command. All other AFS commands such as 'klog', 'kpasswd', 'kas', 'vos',
and 'res' don't need the AFS kernel extensions and can be used, anyway.
Here is a short description of what we can offer:
klog The same as on AFS clients: provides you with an AFS
token. The token is stored in the Kerberos ticket file
/tmp/tkt_<uid> and is seen by all processes owned by
the user with uid <uid>. That means once you have done
the klog all your jobs can make use of it.
unlog To delete the token.
fs The fs command in AFS is the central command to administer
the AFS file-tree. In order to allow you to use AFS without
an AFS-client we added a number of new subcommands:
fs cd Change working directory. Since on the T3E AFS is not known
as a filesystem you can't go there by the ordinary cd-command.
However, it is very comfortable not always to have to enter
the whole long path-name for a file. The name of the current
AFS working directory is stored in a small file
/tmp/afs_cwd_<uid> so that subsequent fs-commands can use it.
Example:
fs cd /afs/ipp/m/hwr
Attention: if you have more than one session on the T3E
all these sessions share the same /tmp/afs_cwd_<uid> file!
fs pwd shows you which your current working directory in AFS is.
fs ls <object> If <object> is a directory or missing you get a short list
of directory entries. If <object> is a file you get
detailed information about mode-bits, owner , change date,
and size for the file. There is one important goodie in this
listing: like on the Cray YMP systems a letter 'm' in the
first place of the modebit information indicates that the
file is migrated!
The option '-long' gives you this kind of display also for
all objects in a directory.
fs write This is the command to copy a file from the T3E into AFS.
Syntax:
fs write <t3e-file> [<afs-file>] [-verbose]
If <afs-file> is missing the file will be created in
the AFS-directory you specified by 'fs cd' with the
same name as <t3e-file>.
fs read This is the command to copy files from AFS to the T3E.
Syntax:
fs read <afs-file> <t3e-file> [-verbose]
fs mkdir <dir> To create a new directory in AFS.
fs rm <object> To remove a file or an empty directory.
Now some commands you know already from MR-AFS on machines with AFS-clients:
fs prefetch <file> Start remigration of a file to random access
storage.
fs fetchq Display queue of waiting fetch requests.
fs getres <files> Display residencies of a file.
fs migrate <file> Allow AFS to migrate this file from random access
storage as soon as possible.
fs help <command> Help for those commands.
Presently this works only along with MR-AFS because in standard
AFS the rpc-call 'RXAFS_Lookup' is only a dummy for compatibility with the
DFS/AFS translator. But for Transarc it should be very easy to fill this
rpc-call with flesh.
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Hartmut Reuter e-mail [EMAIL PROTECTED]
phone +49-89-3299-1328
RZG (Rechenzentrum Garching) fax +49-89-3299-1301
Computing Center of the Max-Planck-Gesellschaft (MPG) and the
Institut fuer Plasmaphysik (IPP)
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