Red Hat GFS 6.0 -, Руководство администратора

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94 Chapter 9. Managing GFS
9.3.1. Usage
umount MountPoint
MountPoint
Specifies the directory where the GFS file system should be mounted.
9.4. GFS Quota Management
File system quotas are used to limit the amount of file-system space a user or group can use. A user or
group does not have a quota limit until one is set. GFS keeps track of the space used by each user and
group even when there are no limits in place. GFS updates quota information in a transactional way
so system crashes do not require quota usages to be reconstructed.
To prevent a performance slowdown, a GFS node synchronizes updates to the quota file only pe-
riodically. The "fuzzy" quota accounting can allow users or groups to slightly exceed the set limit.
To minimize this, GFS dynamically reduces the synchronization period as a "hard" quota limit is
approached.
GFS uses its
gfs_quota
command to manage quotas. Other Linux quota facilities cannot be used
with GFS.
9.4.1. Setting Quotas
Two quota settings are available for each user ID (UID) or group ID (GID): a hard limit and a warn
limit .
A hard limit is the amount space that can be used. The file system will not let the user or group use
more than that amount of disk space. A hard limit value of zero means that no limit is enforced.
A warn limit is usually a value less than the hard limit. The file system will notify the user or group
when the warn limit is reached to warn them of the amount of space they are using. A warn limit value
of zero means that no limit is enforced.
Limits are set using the
gfs_quota
command. The command only needs to be run on a single node
where GFS is mounted.
9.4.1.1. Usage
Setting Quotas, Hard Limit
gfs_quota limit -u User -l Size -f MountPoint
gfs_quota limit -g Group -l Size -f MountPoint
Setting Quotas, Warn Limit
gfs_quota warn -u User -l Size -f MountPoint
gfs_quota warn -g Group -l Size -f MountPoint
User
A user ID to limit or warn. It can be either a user name from the password file or the UID number.