You can control how space is allocated in an NSS pool or volume by restricting the amount of space available to a particular volume, directory, or user. These space restrictions, or quotas, work independently, with the lower value being the most restrictive if all constraints apply. NSS allocates the space as it is needed; the quota does not reserve the space.
The following table indicates quotas supported by NSS on NetWare® and Linux:
If you set a quota to a value equal to or less than the current size of space in use for the specified volume, directory, or user, users cannot add files until enough files are deleted to free up space in the volume, directory, or user files. Users can continue to access existing files for which they are authorized users, but they cannot save them.
As the amount of space consumed by a user’s files approaches the user’s space quota, the user should use caution when saving files. Data loss can occur if the user attempts to save a file that is too large for the remaining unused space.
WARNING:If storing a file would cause a quota to be exceeded, only part of the file is actually saved, resulting in data corruption.
When you create an NSS volume, you have the option of setting a space quota for the volume or letting it grow to the size of the pool. At any time thereafter, you can view and configure the volume quota from the tab in iManager. For information, see Section 18.2, Managing NSS Volume Quotas.
If you set a volume quota to grow to the pool size, you can also add segments to the volume’s pool to expand its size, and, therefore, expand the volume quota.
As a volume nears its quota, automatic controls can be configured to manage space. For information, see Section 24.3, Monitoring Quotas and Space Usage for NSS Pools and Volumes.
Directory quotas limit the space available in an individual NSS directory. To use directory quotas on an NSS volume, you must first enable the Directory Quotas attribute.
IMPORTANT:On Linux, after you enable or disable the Directory Quotas attribute, you must restart eDirectory to enforce the change.
For information about configuring attributes when you create a volume, see Managing NSS Volumes.
For information about setting directory quotas, see Section 18.3, Managing Directory Quotas
User space restrictions limit the space available to a user of the NSS volumes across all directories and files owned by the user. For information about setting user space quotas, see Section 18.4.4, Configuring a User Space Quota.
You must first enable the User Space Quotas attribute on the NSS volume where you want to configure user space restrictions. You can set the attribute at any time. For information about configuring the User Space Quotas attribute for an existing volume, see Modifying Attributes of an NSS Volume.
User space quotas are supported on NetWare and on OES SP1 Linux and later. On Linux, users must be additionally enabled for Linux User Management so that NSS can track file ownership and enforce space consumption. For information about file ownership for NSS volumes on OES Linux, see Section 6.3.6, Enforcing File Ownership and User Space Restrictions.
Quotas are beneficial for systems where you want to control how your storage resources are used. In environments such as a university, where you set up a common work area for a large number of students and you want to limit the space that directory can consume, set a Directory Quota. You might also limit the amount of space an individual user’s work can consume by setting the User Quota.
For example, if a directory’s quota is 500 MB and the user’s quota is 1 GB, the user is limited to up to 500 MB in the specific directory. If the user can access multiple directories, each with a 500 MB quota, the maximum space the user’s work can consume for all directories combined is limited to the user’s 1 GB administrative limit.