Skip to main content

How changing the security style of a qtree affects user quotas

You can apply Access Control Lists (ACLs) on qtrees by using NTFS or mixed security styles, but not by using the other security style. Therefore, changing the security style of a qtree might affect how quotas are calculated. You should always reinitialize quotas after you change the security style of a qtree.

If you change the security style of a qtree from NTFS or mixed to other security style, any ACLs on files in that qtree are ignored and the file usage is charged against the Linux user IDs.

If you change the security style of a qtree from other security style to either mixed or NTFS, the previously hidden ACLs become visible. In addition, any ACLs that were ignored become effective again, and the NFS user information is ignored. If no ACL existed before, the NFS information continues to be used in the quota calculation.
Note
To make sure that quota usages for both Linux and Windows users are properly calculated after you change the security style of a qtree, you must reinitialize quotas for the volume containing that qtree.

Example​

The following example shows how a change in the security style of a qtree results in a different user being charged for the usage of a file in the particular qtree.

Suppose NTFS security is in effect on qtree A, and an ACL gives Windows user corp\joe ownership of a 5 MB file. User corp\joe is charged with 5 MB of disk space usage for qtree A.

Now you change the security style of qtree A from NTFS to other security style. After quotas are reinitialized, Windows user corp\joe is no longer charged for this file; instead, the Linux user corresponding to the UID of the file is charged for the file. The UID could be a Linux user mapped to corp\joe or the root user.