Raw Devices and BR*Tools

The following information is important if you intend to use BR*Tools 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:

Ў        <Raw-Device-Dir> specifies the central directory containing the devices.

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

Ў        <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. BR*Tools checks that the naming convention has been observed.

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 struc<DBSID>.log for each new file added to the database using BRSPACE.

If the database is recovered using BRRECOVER, BRRECOVER uses this structure log to check whether the link structure is still complete and immediately repairs it if not. If a tablespace is extended or a new tablespace is created or dropped, BRSAPCE updates the structure log.

·        Each raw device can contain only one tablespace file, because this is an Oracle requirement. BRSPACE can determine the size of this partition. Therefore, in the case of tablespace extension (adding a file on a raw device), for example, the size of the file is checked automatically if it fits the raw partition.