Raw Devices and SAPDBA (SAP Library - SAP Database Guide: Oracle (BC-DB-ORA-DBA))

Raw Devices and SAPDBA

The following information is important if you intend to use SAPDBA for Oracle with raw devices:

Be sure to observe the SAP naming convention for tablespaces on raw devices:

<SAPDATA_HOME>/sapraw/<TSP>_<Number> ® <Raw-Device-Dir>/<Device>

This is composed as follows:

<Raw-Device-Dir> specifies the central directory containing the devices. This directory can also be specified in the rawdev_dir parameter.

<Device> consists of <DBSID><TSP>_<Number> .

<Number> is the sequence number assigned to the raw devices (or files) belonging to the tablespace.

See also Environment Variables (UNIX).

Each tablespace "file" (held on a raw device) visible to Oracle is a symbolic link to a raw device. SAPDBA checks that the naming convention has been observed.

Example

Tablespace PSAPDOCUD

/oracle/C11/sapraw/docud_1 ® /dev/rdsk/C11docud_1

Compare this with the SAP naming conventions for tablespaces in the file system.

The database link structure is recorded in the structure log struct<DBSID>.log .

If the database check is done using SAPDBA, SAPDBA uses this structure log to check whether the link structure is still complete and immediately repairs it if not. If a tablespace is extended, a new tablespace is created or a tablespace is reorganized with data files, then SAPDBA updates the structure log. See Structure Log.

Each raw device can contain only one tablespace file (this is an Oracle requirement). SAPDBA can set the size of this partition. Therefore, in the case of tablespace extension (adding a file from a raw device), for example, the size of the raw device is determined automatically and is used for the size of the file. See Extending a Tablespace.

It might be sensible to specify the rawdev_dir and blkdev_dir parameters in the init<DBSID>.dba profile.