Re: directory ownership bug in gluster 3.4 & 3.5

[Pranith Kumar Karampuri <pkarampu@xxxxxxxxxx>]

On 09/04/2014 10:45 PM, Pranith Kumar Karampuri wrote:

On 09/04/2014 10:34 PM, John Mark Walker wrote:

Thanks Pranith - has a bug been filed so we can track this?

https://bugzilla.redhat.com/show_bug.cgi?id=1138386

Bug is happening because of synchronization problem between 'distribute' xlator on the mount which created the directory(directory self-heal code path) and the other mount while setting the new uid:gid
For detailed RCA check: https://bugzilla.redhat.com/show_bug.cgi?id=1138386#c4

CCdevs who work on dht

Pranith

Pranith

-JM

On Thu, Sep 4, 2014 at 12:47 PM, Pranith Kumar Karampuri <pkarampu@xxxxxxxxxx> wrote:

hi Peter,
         Sorry for the delay in replying to this mail. I am able to reproduce the bug consistently. Disabling stat-prefetch reduced the number of times the errors come but it hasn't eliminated the issue.

Following the strace output was interesting. The problem always seems to be because the uid is not matching:
stat("/mnt/fuse1/test-target/test1409848960.3", {st_dev=makedev(0, 41), st_ino=12165775161408537538, st_mode=S_IFDIR|0550, st_nlink=2, *st_uid=0*, st_gid=9999, st_blksize=131072, st_blocks=1, st_size=6, st_atime=2014/09/04-22:12:40, st_mtime=2014/09/04-22:12:40, st_ctime=2014/09/04-22:12:40}) = 0

uid is coming as 0 and gid is 9999. If we do a stat after the run is over it is showing things correctly. I am yet to isolate the problem. I will keep you updated once I find something.

Pranith

On 08/22/2014 11:15 PM, Peter Drake wrote:

I have a replicated Gluster setup, 2 servers (fs-1 and fs-2) x 1 brick.  I have two clients (also on fs-1 and fs-2) which mount the Gluster volume at /mnt/gfs (/mnt/gfs type fuse.glusterfs (rw,default_permissions,allow_other,max_read=131072)).  These clients have scripts which perform various file operations.  One operation they perform looks like this (note this is pseudocode, the actual script is PHP):

1. @mkdir(/mnt/gfs/somedir, 0550);

2. chown(1234, /mnt/gfs/somedir);

3. chgrp(1234, /mnt/gfs/somedir);

Note that line 1 may fail on either client because the directory may have been created on the other client.  These errors are suppressed/ignored.  When this operation is performed simultaneously on both clients, it usually succeeds in creating a directory with the expected permissions and ownership.  Intermittently however, we see that these directories are not owned by the expected user and group.

I've created a PHP script which can be run on two clients simultaneously to reproduce the error: https://gist.github.com/pdrakeweb/ae046b4c70a42309be43

The only log entry I can find that appears to be related is from fs-1's mnt-gfs.log file:

[2014-08-22 12:27:57.661778] I [dht-layout.c:640:dht_layout_normalize] 0-test-fs-cluster-1-dht: found anomalies in /test-target/test1408710477.7. holes=1 overlaps=0

This occurs in both Gluster 3.4.1 and 3.5.2 (the only two versions I have tested for this).  I am unable to reproduce the problem on a local (non-gluster) filesystem.  I'd appreciate any insight people might have into what is going on here and whether this is a bug in Gluster.

--

Peter Drake | Cloud Software Engineer |  Acquia

O: 781.238.4236

E: peter.drake@xxxxxxxxxx  |  Skype: pdrakeweb

W: http://www.acquia.com

Address: 25 Corporate Drive 4th Floor, Burlington, MA 01803

Acquia ranked #1 Software Vendor on the 2012 Inc 500

Acquia named One of America’s Most Promising Companies by Forbes

Drupal Sites: http://drupalshowcase.com

Twitter http://www.twitter.com/Acquia

--

Peter Drake | Cloud Software Engineer |  Acquia

O: 781.238.4236

E: peter.drake@xxxxxxxxxx  |  Skype: pdrakeweb

W: http://www.acquia.com

Address: 25 Corporate Drive 4th Floor, Burlington, MA 01803

Acquia ranked #1 Software Vendor on the 2012 Inc 500

Acquia named One of America’s Most Promising Companies by Forbes

Drupal Sites: http://drupalshowcase.com

Twitter http://www.twitter.com/Acquia

_______________________________________________
Gluster-users mailing list
Gluster-users@xxxxxxxxxxx
http://supercolony.gluster.org/mailman/listinfo/gluster-users

_______________________________________________
Gluster-users mailing list
Gluster-users@xxxxxxxxxxx
http://supercolony.gluster.org/mailman/listinfo/gluster-users

_______________________________________________
Gluster-users mailing list
Gluster-users@xxxxxxxxxxx
http://supercolony.gluster.org/mailman/listinfo/gluster-users

_______________________________________________
Gluster-users mailing list
Gluster-users@xxxxxxxxxxx
http://supercolony.gluster.org/mailman/listinfo/gluster-users