Raw I/O Setup Steps

1. Select a shared disk partition of appropriate size for the SAP MaxDB device space.

2. Bind an unused raw device node to this partition. Since this needs to be done every time the machine is rebooted and requires root access, you may want to add the raw bindings to a system initialization file (i.e. rc.local or boot.local). These bindings must be removed from the file once the hierarchy is under LifeKeeper protection. LifeKeeper will re-establish the raw bindings for raw I/O devices that are under LifeKeeper protection. Use the command raw –qa to see which raw device nodes are already in use. For example:

# raw –qa

# raw /dev/raw/raw1 /dev/sda1

3. Set global read permissions on both the raw device controller (/dev/raw/rawctl) and the disk partition on all servers that will protect the database instance.

# chmod a+r /dev/raw/rawctl

4. Set group and user read/write permissions on the raw device on all servers that will protect the database instance.

# chmod 664 /dev/raw/raw1

5. Change the owner of the raw device to the SAP MaxDB OS User for the given database instance on all servers that will protect the database instance.

# chown –R sapdb:sapdb /dev/raw/raw1

6. Add the device space to the database using param_adddevspace or db_adddevspace. Refer to the SAP MaxDB User Manual and/or the Database Manager CLI Manual.