Legato - Solving JBX Misbehavior

L. Weissman
11/03/98

How to correct jukebox problems?

For a variety of reasons, your jukebox may not respond to NetWorker commands as expected.. Often you receive an error message from NetWorker during a backup operation.

Why does this happen?

A very common cause is operator intervention. Manually moving, unloading or loading tapes may cause a discrepancy between NetWorker's information on the status of the jukebox and the actual physical status of the jukebox. On jukeboxes that support barcodes and/or element status, a special 'feature' lets the jukebox know if the door is opened. Since the jukebox has no way of knowing what the operator did while the door was open, it goes into a state which reflects that uncertainty, and in many cases does not function properly until that uncertainty is removed.

Another possible cause is the corruption of the jukebox resource file, nsrjb.res. Corruption may occur to an open nsrjb.res file during a system crash.

Other hardware and software problems may also cause corruption to nsrjb.res or cause the jukebox to Behave as if it were confused or in disarray.

Regardless of the cause, the symptoms indicate one of the following:

• Confusion
• NetWorker and your jukebox do not agree on what tapes are in the jukebox.
• Uncertainty exists to the point of disrupting normal NetWorker operations.
• Hardware or configuration problems exist.

The following steps are in order based upon simplicity, risk and time. Be sure that the first items are done before proceeding to the next items.

If you have manually loaded or unloaded a tape to or from a drive, you can try replacing the tapes in their original configuration and try to get NetWorker to perform the correct operation. In many cases you will still need to reset, re-inventory and/or power cycle the jukebox as described below.

Before you begin

• Check that required NetWorker patches have been installed.
• Verify proper SCSI bus and jukebox driver installation using suitable tools and utilities.
• Verify jukebox configuration.
• Using the NetWorker Administrator's GUI go to the Jukeboxes window. Verify the following data fields against the hardware:
  • Available slots: This field should be a range of slots, i.e. 2-10, as opposed to a single digit.
  • Control port: This field should match the entry used for control port in such commands as pscinfo, jbexercise, etc.

Devices:

Verify that the proper device names are being used, and that the names are physically in the jukebox.

On EXB-210's the first device listed in this field should be the top device in the jukebox. On EXB-60's and 120's they should be listed in order of physical location in the jukebox, from left to right.

Physical slots:

This field should be listed as 1,10 as opposed to 1-10 in 'available slots.
Verify that model and 'number of devices' match the physical jukebox.

Note: If any of the above are incorrect, they must be corrected before continuing.

Volumes:

Verify that the volumes in this field are physically in the jukebox by using the following command:

"nsrjb -Cv "
(Provides a list of Volumes by slot; this should agree with the physical inventory).

If these lists do not agree, your jukebox is "confused" and you need to proceed with the subsequent troubleshooting steps.
Re-initialize element status for jukebox with barcodes and/or element status.

This section may be skipped for jukeboxes that do not support barcodes and/or element-status.

Opening the door may confuse jukeboxes that support barcodes and/or element-status.

If the jukebox door is manually opened, the jukebox immediately marks all the slots as questionable, since it (the jukebox) can not be sure what the user has removed, replaced, or changed. To get past this condition, the jukebox needs to check all of the slots and read the barcodes (if enabled) to verify what is installed in each slot.

To reset element status use either of the following commands:

* "pscinfo -i /dev/sjid1u1" (use correct device name).

* "nsrjb -HE -v" (Resets the jukebox hardware and element status).

If you get an error message, try these commands again. The second try may correct the problem. If errors continue, you should analyze the errors and correct them before proceeding.

Inventory jukebox

For many simple problems, it may only be necessary to re-inventory the contents of the jukebox to de-confuse the jukebox. This is easily done from the command prompt with:

* "nsrjb -I -v"

A successful inventory indicates the jukebox confusion is resolved. Monitor subsequent backups and jukebox operations to insure no other problems occur. There is no need to continue with the subsequent troubleshooting steps.

Reset jukebox hardware

Some problems require a hardware reset to de-confuse the jukebox. Use the following command:

* "nsrjb -H -v"

You may need to follow the hardware reset with the inventory operation listed above. A power recycle may also be necessary to fully reset the jukebox.

Fixing the confused jukebox resource file

The following procedure corrects jukebox confusion by first erasing the existing inventory stored the NetWorker resource file, and then forcing the system to recreate a new inventory.

1. Login to the NetWorker server as root.
2. Start the NetWorker Administrator's GUI.
   • "networker -s <server> -x" (NetWorker version 4.0.2.x)
   • "nwadmin -s server" (NetWorker version 4.1.x)
3. 3. Select the Jukeboxes window.
   • Admin -> Jukeboxes (NetWorker version 4.0.2.x ]
   • Media -> Jukeboxes (NetWorker version 4.1.x)
   • Select View Details.
   • Look for the fields "Loaded Slots" and "Loaded Volumes".
   • Clear contents of both fields, then press the"Change" button.
4. 4. Invoke the command prompt and type:
   • "nsrjb -HE -v" (the 'E' option will reset element status).
     "nsrjb -Iv" (the "I" takes an inventory of the jukebox).

NetWorker and the jukebox should now be synchronized.

Completely reconfiguring the jukebox

If going through the steps listed above does not resolve your jukebox problem, the resource file, nsrjb.res, may be corrupt.

Try the one of the following suggestions to address a potentially corrupted nsrjb.res file.

Suggestion 1:

Recover a previous version of the nsrjb.res file from a backup.

Note: You may need to recover more than one version of nsrjb.res, dependent upon when the corruption actually occurred.

Suggestion 2:

Recreate the nsrjb.res file.

1. Shutdown all NetWorker daemons by typing "nsr_ shutdown -a" from the command prompt.
2. Type "mv /nsr/res/nsrjb.res /nsr/res/nsrjb.res.old" to rename the current nsrjb.res file to nsrjb.res.old.
3. Start the NetWorker daemons by typing "nsrd" at the command prompt.
4. Run "jb_config" from the command prompt to configure the jukebox.
5. Re-enter the jukebox enabler, if necessary.