This information is no longer up to date.

The java part is in process of being revised.

Monitoring and Administration with Java Tools

We are currently in the process of imbedding java into our system as administration and monitoring toolkit. This should not be seen as a general strategy but as an evaluation phase to prove the usability of Java in this context.

To use those tools you must have jdk or jre 1.1.3 or higher installed. The applications and in future time the applets are assembled in $pnfs/tools/jpnfs.jar. You need to add this java archive file to your CLASSPATH variable. The applications are accessible in the jpnfs.apps package. So to start the pnfsSpy monitor discussed below, do the following :

. /usr/etc/pnfsSetup
export CLASSPATH
CLASSPATH=$pnfs/tools/jpnfs.jar:$CLASSPATH

Some of the tools may run on any host having 'pnfs' mounted. On those hosts you may copy the jpnfs.jar whereever you like and set the CLASSPATH variable accordingly. To Start the tool:

java jpnfs.apps.pnfsSpy

The pnfsSpy Monitor

The pnfsSpy monitor may run on any host having any pnfs filesystem mounted. The tool assembles statistical informations about the number of database accesses and is able to display the result as hits/second or total hits since the the tool has been started. There is no further configuration necessary. All informations are taken from the pnfs filesystem itself. When starting the tool you may specify the mountpoint of the pnfs filesystem as first argument:
java jpnfs.apps.pfnsSpy  /pnfs/fs
If omitted, pnfsSpy tries to determine the mountpoint by itself. If it detects more than one pnfs filesystem it gives you the chance to chose one of them.
After pnfsSpy could verify that the filesystem is pnfs, it scans all databases and extracts the active ones. The next step is the determination of the filesystems update time of regular file contents and attributes. For OSs other then Linux this intervall is in the order of seconds, for Linux it may take a minute and more. To run the tool it's recommended to descrease the update time to about 5 seconds in the mount command. pnfsSpy displays a highlighted messages after finding the update intervall. After that one horizontal bar should be displayed per database. If the bars don't contain the name of the databases the display can be enlarged. If the bars are large enough to hold the default font the names should appear. The display is updated with the determined update intervall. The Option menu allows an autoscale or a manual scaling of the hits/second. Changes in the option menu may only take effect after the update intervall has expired. The topline of the display shows the parameters currently active.