PRIMECLUSTER Global File Services Configuration and Administration Guide 4.1 (Linux)

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.

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

• The type of disk class to which the logical volume belongs is 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.

When logical volumes of GDS are stopped, access is totally prohibited. Thus, commands of the GFS Shared File System can be used only when logical volumes of GDS are active.

• Set the stripe width of 256 blocks or more when the disk stripe of GDS is being used as GFS Shared File System.
• Do not expand the volume of GDS including in the GFS Shared File System. When volume expansion is performed, using the file system becomes impossible because the volume size changes and reading the copy of super block and partition configuration data on GFS Shared File System becomes impossible.

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

For the operations of logical volumes of GDS, refer to the description of volume operations under "Operation using Global Disk Services Management View" in the "PRIMECLUSTER Global Disk Services Configuration and Administration Guide".