# output

Writes the external plugin’s standard output and standard error to a helper log file for debugging.

This parameter applies to Support module for external message modification modules.

Name:

  output

Scope:

  input

Type:

  string

Default:

  none

Required?:

  no

Introduced:

  8.3.0

## Description

This is a debug aid. If set, this is a filename where the combined standard output and standard error stream from the plugin is logged before rsyslog parses it as a JSON response. Note that the output is also being processed as usual by rsyslog. Setting this parameter thus gives insight into the internal processing that happens between plugin and rsyslog core.

Warning

The external program’s standard error stream is captured together with standard output. Any data written to stderr is intermingled with the JSON response from stdout and will likely cause parsing failures. Ensure the external program does not write to stderr.

## Input usage

    module(load="mmexternal")

    action(
        type="mmexternal"
        binary="/path/to/mmexternal.py"
        output="/var/log/mmexternal-debug.log"
    )

## See also

See also Support module for external message modification modules.

Support: rsyslog Assistant | GitHub Discussions | GitHub Issues: rsyslog source project

Contributing: Source & docs: rsyslog source project

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