5.6 HP StorageWorks X9000 File Serving Software User Guide (TA768-96035, June 2011)

3 Setting up quotas
Quotas can be assigned to individual users or groups, or to a directory tree. Individual quotas
limit the amount of storage or the number of files that a user or group can use in a file system.
Directory tree quotas limit the amount of storage and the number of files that can be created on a
file system located at a specific directory tree.
Although it is best to set up quotas when you create a file system, you can configure them at any
time. You can assign quotas to a user, group, or directory on the management console or from
the CLI. You can also import quota information from a file.
If a user has a user quota and a group quota for the same file system, the first quota reached takes
precedence.
The existing quota configuration can be exported to a file at any time.
NOTE: HP recommends that you export the quota configuration and save the resulting file
whenever you update quotas on your cluster.
How quotas work
A quota is delimited by hard and soft storage limits for both the megabytes of storage and the
number of files allotted to a user, group, or directory tree. The hard limit specifies the maximum
allotted storage in terms of file size and number of files. The soft limit specifies the number of
megabytes or files that, when reached, causes the file serving node to start a countdown timer.
The timer runs until either the hard storage limit is reached or seven days elapse. When the timer
stops, the user, group, or directory tree for which the quota was set cannot store any more data,
and the system issues Disk quota exceeded messages at each write attempt.
NOTE: Quota statistics are updated on a regular basis (at one-minute intervals). At each update,
the file and storage usage for each quota-enabled user, group, or directory tree is queried, and
the result is distributed to all file serving nodes. Users or groups can temporarily exceed their quota
if the allocation policy in effect for a file system causes their data to be written to different file
serving nodes during the statistics update interval. In this situation, it is possible for the storage
usage visible to each file serving node to be below or at the quota limit while the aggregate storage
use exceeds the limit.
There is a delay of several minutes between the time a command to update quotas is executed
and when the results are displayed by the ibrix_edquota -l command. This is normal behavior.
Enabling quotas on a file system
Before you can set quota limits, quotas must be enabled. If you did not enable quotas when you
created the file system, unmount the file system and then take one of these actions:
• On the management console, select the file system and then select Quotas from the lower
Navigator. On the Quota Summary page, click Enable.
• From the CLI, run the following command:
<installdirectory>/bin/ibrix_fs -q -E -f FSNAME
Setting user and group quotas
Before configuring quotas, the quota feature must be enabled on the file system and the file system
must be mounted.
How quotas work 19