[LU-7842] ACL's applied over NFS are not consistent when looping file operations

Related — Thu, 14 Jun 2018 21:41:20 +0000

We are experiencing an issue where on a lustre client we do not see the issue, but exported over NFS we see this issue on one of our three production lustre file systems. We cannot reproduce this issue on any other system, but is causing us production issues on our oldest lustre instance.

Running the script attached over NFS after a few iterations we hit the following issue:

[joe59240@vws250 joe59240]$ /dls/tmp/joe59240/stresstest
....mkdir: cannot create directory `5': Permission denied

Each "." is an iteration of the loop as you will see in the script

This persists for maybe as long as five seconds before files can be written to the folder again and the script runs.

At the moment we have not ever had the script run to completion, but on other lustre file systems we can run it hundreds of times to completion.
The file system has many different NFS exporters each exporting a different folder in the root of the file system. As is common practice on all other systems at Diamond. We can re produce this on all exporters attached to this particular file system.

We are thinking after a number of weeks looking at the issue that it is not the exporter as this is across all servers that export lustre but down to the interaction between FS and NFS.

We have put in a few sleeps in the script to try and identify if there is a buffering issue where we are modifying or deleting before a flush to disk. But this has not improved the symptoms.

Would it be possible to advise further debugging?

Whamcloud Community JIRA

[LU-7842] ACL's applied over NFS are not consistent when looping file operations