# Module Parameters

The following parameters define default settings for the omfwd module. These values are used by all omfwd actions unless explicitly overridden by action parameters.

Note

- Module parameters are configured by loading the built-in module with `module(load="builtin:omfwd" ...)`.

- Action parameters (inside `action(type="omfwd" ...)`) take precedence over these defaults when both are set.

## List of Module Parameters

### Template

type | default | mandatory | `obsolete legacy` directive
--- | --- | --- | ---
word | RSYSLOG_TraditionalForwardFormat | no | `$ActionForwardDefaultTemplate`

Sets a custom default template for this module.

### iobuffer.maxSize

type | default | mandatory | `obsolete legacy` directive
--- | --- | --- | ---
integer | full size | no | none

The iobuffer.maxSize parameter sets the maximum size of the I/O buffer used by rsyslog when submitting messages to the TCP send API. This parameter allows limiting the buffer size to a specific value and is primarily intended for testing purposes, such as within an automated testbench. By default, the full size of the I/O buffer is used, which depends on the rsyslog version. If the specified size is too large, an error is emitted, and rsyslog reverts to using the full size.

Note

The I/O buffer has a fixed upper size limit for performance reasons. This limitation allows saving one `malloc()` call and indirect addressing. Therefore, the `iobuffer.maxSize` parameter cannot be set to a value higher than this fixed limit.

Note

This parameter should usually not be used in production environments.

#### Example

    module(load="builtin:omfwd" iobuffer.maxSize="8")

In this example, a very small buffer size is used. This setting helps force rsyslog to execute code paths that are rarely used in normal operations. It allows testing edge cases that typically cannot be tested automatically.

Note that contrary to most other modules, omfwd is a built-in module. As such, you cannot “normally” load it just by name but need to prefix it with “builtin:” as can be seen above!

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