Sun Java System Application Server Enterprise Edition 8.1 2005Q2 High Availability Administration Guide

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## Viewing and Modifying Configuration Attributes

You can view and modify database configuration attributes with the `hadbm get and hadbm set` commands, respectively.

### Getting the Values of Configuration Attributes

To get the values of configuration attributes, use the `hadbm get` command. For a list of valid attributes, see Configuration Attributes. The command syntax is:

    hadbm get attribute-list | --all
    [dbname]
    [--adminpassword=password | --adminpasswordfile=file]
    [--agent=maurl]

The dbname operand specifies the database name. The default is `hadb`.

The attribute-list operand is a comma-separated or quote-enclosed space-separated list of attributes. The `--all` option displays values for all attributes. For a list of all attributes for `hadbm get`, see Configuration Attributes.

See General Options for a description of command options.

##### Example 3–4 Example of using hadbm get

    hadbm get JdbcUrl,NumberOfSessions

### Setting the Values of Configuration Attributes

To set the values of configuration attributes, use the `hadbm set` command. For a list of valid attributes, see Configuration Attributes

    hadbm set [dbname] attribute
    =value[,attribute=
    value...]
     [--adminpassword=password | --adminpasswordfile=file]
     [--agent=maurl]

The dbname operand specifies the database name. The default is `hadb`.

The attribute=value list is a comma-separated or quote-enclosed space-separated list of attributes.

See General Options for a description of command options.

If this command executes successfully, it restarts the database in the state it was in previously, or in a better state. For information about database states, see Getting the Status of HADB restart the HADB as described in Restarting a Database.

You cannot set the following attributes with `hadbm set`. Instead, set them when you create a database (see Creating a Database).

- DatabaseName

- DevicePath

- HistoryPath

- NumberOfDatadevices

- Portbase

- JdbcUrl (its value is set during database creation based on the `--hosts` and `--portbase` options).

Note –

Using `hadbm set` to set any configuration attribute, except `ConnectionTrace` or `SQLTraceMode`, causes a rolling restart of HADB. In a rolling restart, each node is stopped, and started with the new configuration, one at a time; HADB services are not interrupted.

If you set `ConnectionTrace` or `SQLTraceMode`, no rolling restart occurs, but the change only takes effect for new HADB connections made from an Application Server instance.

### Configuration Attributes

The following table lists the configuration attributes that you can modify with `hadbm set` and retrieve with `hadbm get`.

Table 3–8 Configuration Attributes

Attribute | Description | Default | Range
--- | --- | --- | ---
ConnectionTrace | If true, records a message in the HADB history files when a client connection (JDBC, ODBC) is initiated or terminated. | False | True or False
CoreFile | Do not change the default value. | False | True or False
DatabaseName | Name of the database. | hadb |
DataBufferPoolSize | Size of the data buffer pool allocated in shared memory. | 200MB | 16 - 2047 MB
DataDeviceSize | Specifies the device size for the node. For information on the recommended `DataDeviceSize`, see Specifying Device Size The maximum value is the smaller of 256GB or the maximum operating system file size. The minimum value is: (4 x LogbufferSize + 16MB) / n where n is number of data devices. | 1024MB | 32 - 262144 MB
PackageName | Name of HADB software package used by the database. | V4.x.x.x | None
DevicePath | Location of the devices. Devices are: Data device (`DataDevice`) Node internal log device (`NiLogDevice`) Relational algebra query device (`RelalgDevice`) | Solaris and Linux: `/var/opt/SUNWhadb` Windows: `C:\Sun\AppServer\SUNWhadb\vers`, where vers is the HADB version number. |
EagerSessionThreshold | Determines whether normal or eager idle session expiration is used. In normal idle session expiration, sessions that are idle for more than `SessionTimeout` seconds are expired. When the number of concurrent sessions exceeds the `EagerSessionThreshold` percentage of the maximum number of sessions, sessions that are idle for more than `EagerSessionTimeout` seconds are expired. | Half of NumberOfSessions attribute | 0 - 100
EagerSessionTimeout | The time in seconds a database connection can be idle before it expires when eager session expiration is used. | 120 seconds | 0-2147483647 seconds
EventBufferSize | Size of the event buffer, where database events are logged. If set to `0`, no event buffer logging is performed. During failures, the event buffer is dumped. This gives valuable information on the cause of the failures and is useful during trial deployment. Writing events to memory has a performance penalty. | `0 MB` | 0-2097152 MB
HistoryPath | Location of the HADB history files, which contain information, warnings, and error messages. This is a read-only attribute. | Solaris and Linux: `/var/opt/SUNWhadb` Windows: REPLACEDIR (replaced by the actual URL at runtime.) |
InternalLogbufferSize | Size of the node internal log device, which keeps track of operations related to storing data. | 12MB | 4 - 128 MB
JdbcUrl | The JDBC connection URL for the database. This is a read-only attribute. | none |
LogbufferSize | Size of the log buffer, which keeps track of operations related to data. | 48MB | 4 - 2048 MB
MaxTables | Maximum number of tables allowed in an HADB database. | 1100 | 100 - 1100
NumberOfDatadevices | Number of data devices used by an HADB node. This is a read-only attribute. | 1 | 1 - 8
NumberOfLocks | Number of locks allocated by an HADB node. | 50000 | 20000-1073741824
NumberOfSessions | Maximum number of sessions (database connections) that can be opened for an HADB node. | 100 | 1 - 10000
PortBase | Base port number used to create different port numbers for different HADB processes. This is a read-only attribute. | 15200 | 10000 - 63000
RelalgDeviceSize | Size of the device used in relational algebra queries. | 128 MB | 32 - 262144 MB
SessionTimeout | Amount of time a database connection can be idle before it expires when normal session expiration is used. | 1800 seconds | 0-2147483647 seconds
SQLTraceMode | Amount of information about executed SQL queries written to the history files. If `SHORT`, login and logout of SQL sessions are recorded. If `FULL`, all SQL queries being prepared and executed, including parameter values, are recorded. | NONE | NONE/SHORT/ FULL
StartRepairDelay | Maximum time a spare node allows for a failed active node to perform a node recovery. If the failed node cannot recover within this time interval, the spare node starts copying data from the failed node’s mirror and becomes active. Changing the default value is not recommended. | 20 seconds | 0 - 100000 seconds
StatInterval | Interval at which an HADB node writes throughput and response time statistics to its history file. To disable, set to 0. Here is an example of a statistics line: `Req-reply time: # 123, min= 69 avg= 1160 max= 9311 %=100.0` The number after the has sign (`#)` is the number of requests serviced over the `StatInterval`. The next three numbers are the minimum, average, and maximum time in microseconds taken by transactions completed over the `StatInterval`. The number afer the percent sign ( `%)` is the number of transactions completed successfully within 15 milliseconds over the `StatInterval`. | 600 seconds | 0 - 600 seconds
SyslogFacility | Facility used when reporting to `syslog`. The `syslog` daemon should be configured (see `man syslogd.conf` for details). Use a facility that is not used by other applications running on the same machine. Set to `none` to disable `syslog` logging. | local0 | local0, local1, local2, local3, local4, local5, local6, local7, kern, user, mail, daemon, auth, syslog, lpr, news, uucp, cron, none
SysLogging | If true, an HADB node writes information to the operating system’s `syslog` files. | True | True or False
SysLogLevel | Minimum level of HADB message saved to operating system’s `syslog` files. All messages of that level or higher will be logged. For example, “info” logs all messages. | warning | nonealert errorwarninginfo
SyslogPrefix | Text string inserted before all `syslog` messages written by the HADB. | hadb -dbname |
TakeoverTime | Time between when a node fails and when its mirror takes over. Do not change the default value. | 10000 (milliseconds) | 500 - 16000 milliseconds

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