HP Serviceguard Extension for RAC (SGeRAC) Volume Planning with Slvm, Storage Planning with CFS

Volume Planning with SLVM

Storage capacity for the Oracle database must be provided in the form of logical volumes located in shared volume groups. The Oracle software requires at least two log files for each Oracle instance, several Oracle control files and data files for the database itself. For all these files, Serviceguard Extension for RAC uses HP-UX raw logical volumes located in volume groups that are shared between the nodes in the cluster. High availability is achieved by using high availability disk arrays in RAID modes. The logical units of storage on the arrays are accessed from each node through multiple physical volume links (PV links, also known as alternate links), which provide redundant paths to each unit of storage. Fill out a Logical Volume worksheet to provide logical volume names for logical volumes that you will create with the lvcreate command. The Oracle DBA and the HP-UX system administrator should prepare this worksheet together. Create entries for shared volumes only. For each logical volume, enter the full pathname of the raw logical volume device file. Be sure to include the desired size in MB. Following is a sample worksheet filled out. However, this sample is only representative. For different versions of the Oracle database, the size of files are different. Refer to Appendix B: “Blank Planning Worksheets”, for samples of blank worksheets. Make as many copies as you need. Fill out the worksheet and keep it for future reference.

Storage Planning with CFS

With CFS, the database software, database files (control, redo, data files), and archive logs may reside on a cluster file system visible by all nodes. Also, the OCR and vote device can reside on CFS directories.

The following software needs to be installed in order to use this configuration:

•SGeRAC

•CFS

CFS and CVM are not supported on all versions of HP-UX (on HP-UX releases that support them. See “About Veritas CFS and CVM from Symantec” (page 15)).

CAUTION: Once you create the disk group and mount point packages, you must administer the cluster with CFS commands, including cfsdgadm, cfsmntadm, cfsmount, and cfsumount. You must not use the HP-UX mount or umount command to provide or remove access to a shared file system in a CFS environment. Using these HP-UX commands under these circumstances is not supported. Use cfsmount and cfsumount instead.

If you use the HP-UX mount and umount commands, serious problems could occur, such as writing to the local file system instead of the cluster file system. Non-CFS commands could cause conflicts with subsequent CFS command operations on the file system or the Serviceguard packages, and will not create an appropriate multi-node package, which means cluster packages will not be aware of file system changes.

NOTE: For specific CFS Serviceguard Storage Management Suite product information refer to your version of the HP Serviceguard Storage Management Suite Release Notes.

Volume Planning with CVM

Storage capacity for the Oracle database must be provided in the form of volumes located in shared disk groups. The Oracle software requires at least two log files for each Oracle instance, several Oracle control files, and data files for the database itself. For all these files, Serviceguard Extension for RAC uses HP-UX raw volumes, which are located in disk groups that are shared between the nodes in the cluster. High availability is achieved by using high availability disk arrays in RAID nodes. The logical units of storage on the arrays are accessed from each node through multiple physical volume links via DMP (Dynamic Multipathing) that provides redundant paths to each unit of storage.

Planning Storage for Oracle 10g/11gR1/11gR2 RAC 31