D
Heterogeneous Services Initialization Parameters

The Oracle database server initialization parameters in the init.ora file are distinct from heterogeneous services (HS) initialization parameters. Set HS parameters in the initialization parameter file using an agent-specific mechanism, or set them in the Oracle data dictionary using the DBMS_HS package.

This appendix contains information about the following Heterogeneous Services initialization parameters:

The HS initialization parameter file must be available when the gateway is started. During installation, the following default HS initialization parameter file is created:

$ORACLE_HOME/tg4ifmx/admin/inittg4ifmx.ora

where $ORACLE_HOME is the directory under which the gateway is installed.

HS Initialization Parameter File Syntax

The syntax for the initialization parameter file is as follows:

The file is a sequence of commands.
Each command should start on a separate line.
End of line is considered a command terminator (unless escaped with a backslash).
Each command can have one of the following forms:
1. <param> = <value>
2. set <param> = <value>
3. private <param> = <value>
4. set private <param> = <value>
where:

<param> is an initialization parameter name.

<value> is the initialization parameter value.

'set' and 'private' are keywords.
The keywords 'set' and 'private' are reserved. You cannot use either as an initialization parameter name. The 'set' keyword indicates that the initialization parameter should be set as an environment variable in the agent. The 'private' keyword indicates that the initialization parameter should be private to the agent and should not be uploaded to the server. Most initialization parameters should not be private. If, however, you are storing something sensitive like a password in the initialization parameter file, then you may not want it uploaded to the server because the initialization parameters and values are not encrypted when uploaded. Making these initialization parameters private prevents the upload from happening.
An initialization parameter name is a string of characters starting with a letter and consisting of letters, digits and underscores. Initialization parameter names are case sensitive.
An initialization parameter value is either:
1. A string of characters that does not contain any backslashes, white space or double quotation marks (")
2. A quoted string beginning with a double quotation mark and ending with a double quotation mark. The following can be used inside a quoted string:
  - backslash (\) is the escape character
  - \n inserts a newline
  - \t inserts a tab
  - \" inserts a double quotation mark
  - \\ inserts a backslash
  A backslash at the end of the line continues the string on the next line. If a backslash precedes any other character then the backslash is ignored.

If there is a syntax error in an initialization parameter file, none of the settings take effect.

HS_FDS_CONNECT_INFO

Default value: none

Range of values: Not Applicable

Specifies the information needed to connect to the Informix database.

This is a required parameter, whose format is:

HS_FDS_CONNECT_INFO=database_name@server_name

where:

database_name is the name of the database and server_name is the name of the server machine for the Informix data.

The entries for both the database_name and server_name are case-sensitive.

If you specify only database_name, omitting server_name, the gateway binds to the database residing on the local Informix server (as specified in the environment variable INFORMIXSERVER).

HS_FDS_RECOVERY_ACCOUNT

Default value: RECOVER

Range of values: any valid password

Specifies the name of the recovery account used for the commit-confirm transaction model. An account with user name and password must be set up at Informix. For more information about the commit-confirm model, see the HS_FDS_TRANSACTION_MODEL parameter.

The name of the recovery account is case-sensitive.

HS_FDS_RECOVERY_PWD

Default value: RECOVER

Range of values: any valid password

Specifies the password of the recovery account used for the commit-confirm transaction model set up at Informix. For more information about the commit-confirm model, see the HS_FDS_TRANSACTION_MODEL parameter.

The name of the password of the recovery account is case-sensitive.

HS_FDS_TRACE_LEVEL

Default value: OFF

Range of values: OFF, ON

Specifies whether error tracing is turned on or off for gateway connectivity.

The following values are valid:

OFF disables the tracing of error messages.
ON enables the tracing of error messages that occur when you encounter problems. The results are written to a gateway connectivity log file, in $ORACLE_HOME/TG4IFMX/LOG.

HS_FDS_TRANSACTION_LOG

Default value: HS_TRANSACTION_LOG

Range of values: any valid table name

Specifies the name of the table created in the Informix database for logging transactions. For more information about the transaction model, see the HS_FDS_TRANSACTION_MODEL parameter.

HS_FDS_TRANSACTION_MODEL

Default value: COMMIT_CONFIRM

Range of values: COMMIT_CONFIRM, READ_ONLY or SINGLE_SITE

Specifies the type of transaction model that is used when the Informix database is updated by a transaction.

The following values are possible:

COMMIT_CONFIRM provides read and write access to the Informix database and allows the gateway to be part of a distributed update. To use the commit-confirm model, the following items must be created in the Informix database:
- Transaction log table. The default table name is HS_TRANSACTION_LOG. A different name can be set using the HS_FDS_TRANSACTION_LOG parameter. The transaction log table must be granted SELECT, DELETE, and INSERT privileges set to public.
- Recovery account. The account name is assigned with the HS_FDS_RECOVERY_ACCOUNT parameter.
- Recovery account password. The password is assigned with the HS_FDS_RECOVERY_PWD parameter.
READ_ONLY provides read access to the Informix database.
SINGLE_SITE provides read and write access to the Informix database. However, the gateway cannot participate in distributed updates.

D Heterogeneous Services Initialization Parameters