# Message Modification Modules

Message modification modules are used to change the content of messages being processed. They can be implemented using either the output module or the parser module interface. From the rsyslog core’s point of view, they actually are output or parser modules, it is their implementation that makes them special.

- IP Address Anonymization Module (mmanon)
- mmcount
- MaxMind/GeoIP DB lookup (mmdblookup)
- Support module for external message modification modules
- Fields Extraction Module (mmfields)
- JSON/CEE Structured Content Extraction Module (mmjsonparse)
- Log Message Normalization Module (mmnormalize)
- RFC5424 structured data parsing module (mmpstrucdata)
- mmrfc5424addhmac
- mmrm1stspace: First Space Modification Module
- Number generator and counter module (mmsequence)
- mmsnmptrapd message modification module
- Fix invalid UTF-8 Sequences (mmutf8fix)