1.8.4 Notes on use of logical volumes of GDS

GDS is volume management software designed to improve the availability and operation manageability of information stored on disk units of the Storage Area Network (SAN). Various kinds of access controls can be performed on the logical volumes of GDS to protect data against damage due to unauthorized access.

See

For the operations of disk classes to which logical volumes of GDS belong, refer to the description of Class operation of "Operation" "GDS Management View" in "PRIMECLUSTER Global Disk Services Configuration and Administration Guide."
For the operations of logical volumes of GDS, refer to the description of Volume operation of "Operation" "GDS Management View" in "PRIMECLUSTER Global Disk Services Configuration and Administration Guide."

1.8.4.1 Notes on setting of logical volumes of GDS

To use a logical volume of GDS in the GFS Shared File System, make the following settings:

The disk class to which the logical volume belongs is of type: "shared".
All nodes sharing the GFS Shared File System are specified in the scope of the disk cluster to which the logical volume belongs.
When the attribute lock mode of the logical volume is lock=off, the volume is started automatically.
The attribute access mode of the logical volume is set as read-write.

To use the GFS Shared File Systems, logical volumes of GDS must be ACTIVE. If they are STOP, all accesses to the shared file systems will be prohibited.

Note

If you create the GFS Shared File System on GDS-striped logical volumes, set the width of the stripe group to 256 blocks or more.

Note

Do not use online volume expansion for the logical volume of GDS that is including GFS Shared File System. Because the copy of the super block and of the partition configuration information of the GFS Shared File System cannot be read when the size of the logical volumes of GDS is changed by the online volume expansion, the GFS Shared File System cannot be used.
If you want to expand the GFS Shared File System, add an unoccupied logical volume partition, or create a new logical volume and add it.

1.8.4.2 Notes when using logical volumes of GDS that were used in a file system other than GFS

If the logical volume of GDS had been used for a file system other than GFS before, clear 1 MB from the beginning of it with dd(1) to zero before using it for a GFS Shared File System.

The execution example is shown below.

# dd bs=1M count=1 if=/dev/zero of=/dev/sfdsk/gfs01/dsk/volume01

See

For details of dd(1), see the online manual page.