This parameter specifies a location for DB2® databases to find log files needed for a
rollforward operation, as well as where to store active log files
retrieved from the archive. It also gives a location for finding and
storing log files needed for using db2ReadLog API.
- Configuration type
- Database
- Parameter type
- Configurable online
- Propagation class
- Immediate
- Default [range]
- NULL [any valid path ]
This parameter can be used for several functions,
depending on your logging requirements.
- This parameter allows you to specify a location for DB2 databases to find log files that are needed
for a rollforward operation. It is similar to the OVERFLOW
LOG PATH option on the ROLLFORWARD command.
Instead of always specifying OVERFLOW LOG PATH on
every ROLLFORWARD command, you can set this configuration
parameter once. However, if both are used, the OVERFLOW
LOG PATH option will overwrite the overflowlogpath configuration
parameter, for that particular rollforward operation.
- If logsecond is set to -1, overflowlogpath allows
you to specify a directory for DB2 to
store active log files retrieved from the archive. (Active log files
have to be retrieved for rollback operations if they are no longer
in the active log path). Without overflowlogpath, DB2 databases will retrieve the
log files into the active log path. Using overflowlogpath allows
you to provide additional resource for DB2 databases
to store the retrieved log files. The benefit includes spreading the
I/O cost to different disks, and allowing more log files to be stored
in the active log path.
- If you need to use the db2ReadLog API (prior
to DB2 Version 8, db2ReadLog was
called sqlurlog) for replication, for example, overflowlogpath allows
you to specify a location for DB2 databases
to search for log files that are needed for this API. If the log file
is not found (in either the active log path or the overflow log path)
and the database is configured with userexit enabled, DB2 will retrieve the log file. overflowlogpath also
allows you to specify a directory for DB2 databases
to store the log files retrieved. The benefit comes from reducing
the I/O cost on the active log path and allowing more log files to
be stored in the active log path.
- If you have configured a raw device for the active log path, overflowlogpath must
be configured if you want to set logsecond to -1,
or if you want to use the db2ReadLog API.
- You can specify a location for DB2 databases to retrieve log files that are
required for a BACKUP DATABASE INCLUDE LOGS operation.
To
set overflowlogpath, specify a string of up to
242 bytes. The string must point to a path name, and it must be a
fully qualified path name, not a relative path name. The path name
must be a directory, not a raw device. You cannot specify overflowlogpath as
an empty string.
Note: In a partitioned database environment, the node number
is automatically appended to the path, for example, /home/dbuser/dblogs/NODE0000/.
This is done to maintain the uniqueness of the path in multiple logical
node configurations.