du: WARNING: Circular directory structure.

• Article Type: General
• Product: Aleph
• Product Version: 20

Problem Symptoms:
The unix "du" (disk usage) command gives following message repeatedly:

du: WARNING: Circular directory structure.
This almost certainly means that you have a corrupted file system.
NOTIFY YOUR SYSTEM MANAGER.
The following directory is part of the cycle: 'exlibris/.snapshot/...'

Cause:
This is a Red Hat / Netapp known issue (please read below) due to the B2D snapshot subfolder that have been created.

On Linux, it is not possible to have directory hardlinks on the same filesystem, but obviously it is possible on NetApp servers. du is not expected to handle cases that are not possible, and gives a warning.

Resolution:
There is no "file corruption" here and no reason to worry. If seen in Red Hat / Netapp, ignore. If seen on other, report to System Administrator.