Unmounting A File System; Special Considerations When Mounting Gfs File Systems - Red Hat ENTERPRISE LINUX 5 - GLOBAL FILE SYSTEM Manual

Option
upgrade
errors=panic|withdraw
Table 3.2. GFS-Specific Mount Options

3.3. Unmounting a File System

The GFS file system can be unmounted the same way as any Linux file system — by using the
umount command.
Note
The umount command is a Linux system command. Information about this command can
be found in the Linux umount command man pages.
Usage
umount MountPoint
MountPoint
Specifies the directory where the GFS file system should be mounted.
3.4. Special Considerations when Mounting GFS File
Systems
GFS file systems that have been mounted manually rather than automatically through an entry in the
fstab file will not be known to the system when file systems are unmounted at system shutdown. As
a result, the GFS script will not unmount the GFS file system. After the GFS shutdown script is run, the
standard shutdown process kills off all remaining user processes, including the cluster infrastructure,
and tries to unmount the filesystem. This unmount will fail without the cluster infrastructure and the
system will hang.
To prevent the system from hanging when the GFS file systems are unmounted, you should do one of
the following:
• Always use an entry in the fstab file to mount the GFS file system.
Description
Note: This option is turned on automatically if
lock_nolock locking is specified; however, you can
override it by using the ignore_local_fs option.
Upgrade the on-disk format of the file system so that it
can be used by newer versions of GFS.
When errors=panic is specified, file system errors
will cause a kernel panic. The default behavior, which
is the same as specifying errors=withdraw, is for
the system to withdraw from the file system and make
it inaccessible until the next reboot; in some cases the
system may remain running. For information on the
GFS withdraw function, see
Withdraw Function".
Unmounting a File System
Section 3.16, "The GFS
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