Accept License Agreements

This app is provided by a third party and your right to use the app is in accordance with the license provided by that third-party licensor. Splunk is not responsible for any third-party apps and does not provide any warranty or support. If you have any questions, complaints or claims with respect to this app, please contact the licensor directly.

Thank You

Downloading Protocol Data Inputs
MD5 checksum (protocol-data-inputs_13.tgz) a82c497822649ce25308b597f3dc4516 MD5 checksum (protocol-data-inputs_12.tgz) 43edecd8d1e7c61becd87630838fa25e MD5 checksum (protocol-data-inputs_11.tgz) 67bcb1fada0d8267c5492730d26cfc5d MD5 checksum (protocol-data-inputs_10.tgz) df17a90225308094ff77d0f36aa09aed MD5 checksum (protocol-data-inputs_07.tgz) 30a3635a47e801dcef8b49e192c1bf59 MD5 checksum (protocol-data-inputs_06.tgz) dcf125267b2fb0754579d0925d5d2270 MD5 checksum (protocol-data-inputs_051.tgz) 97e4cad2fe5ded25bfebec8d6f93564f MD5 checksum (protocol-data-inputs_05.tgz) 6ac11297c9ade8319a447685d1f0ca24
To install your download
For instructions specific to your download, click the Details tab after closing this window.

Flag As Inappropriate

Protocol Data Inputs

This is a Splunk Add-On for receiving data via a number of different data protocols such as TCP , TCP(s) ,HTTP(s) PUT/POST/File Upload , UDP , Websockets , SockJS. The event driven , non blocking , asynchronous architecture is designed to handle connections and data at scale. The polyglot event bus allows you to declaratively plug in custom data handlers in numerous different languages(Java , Javascript , Python, Groovy , Scala , Clojure , Ruby etc..) to pre-process raw data before indexing in Splunk. Secure transport channels also allow for client certificate authentication.

Protocol Data Inputs v1.3


This is a Splunk Add-On for receiving data via a number of different data protocols.


  • TCP
  • TCP w/ TLS , optional client certificate authentication
  • UDP (unicast and multicast)
  • HTTP (PUT and POST methods only , data in request body & file uploads)
  • HTTPS (PUT and POST methods only , data in request body & file uploads) , optional client certificate authentication
  • Websockets
  • SockJS

But we already have TCP/UDP natively in Splunk

Yes we do. And by all means use those. But if you want to perform some custom data handling and pre-processing
of the received data before it gets indexed (above and beyond what you can accomplish using Splunk conf files) ,
then this Modular Input presents another option for you.
Furthermore , this Modular Input also implements several other protocols for sending data to Splunk.


This Modular Input utilizes VERTX.IO version 2.1.4 under the hood.

This framework provides for an implementation that is :

  • asynchronous
  • event driven (reactive)
  • polyglot (code custom data handlers in java , javascript , groovy , scala , clojure , ruby , python , any JVM lang with a vertx module)
  • non blocking IO
  • scales over all your available cores
  • can serve high volumes of concurrent client connections

Polyglot Custom Data Handling / Pre Processing

The way in which the Modular Input processes the received raw data is entirely pluggable with custom implementations should you wish.

This allows you to :

  • pre process the raw data before indexing
  • transform the data into a more optimum state for Splunk
  • perform custom computations on the data that the Splunk Search language is not the best fit for
  • decode binary data (encrypted , compressed , images , proprietary protocols , EBCDIC etc....)
  • enforce CIM compliance on the data you feed into the Splunk indexing pipeline
  • basically do anything programmatic to the raw byte data you want

To do this you code a Vertx "Verticle" to handle the received data.

These data handlers can be written in numerous JVM languages.

You then place the handler in the $SPLUNK_HOME/etc/apps/protocol_ta/bin/datahandlers directory.

On the Splunk config screen for the Modular Input there is a field where you can then specify the name of this handler to be applied.

If you don't need a custom handler then the default handler com.splunk.modinput.protocolverticle.DefaultHandlerVerticle will be used.

To get started , you can refer to the default handler examples in the datahandlers directory.

Supported languages and file extensions

  • Javascript .js
  • CoffeeScript .coffee
  • Ruby .rb
  • Python .py
  • Groovy .groovy
  • Java .java (compiled to .class)
  • Scala .scala
  • Clojure .clj
  • PHP .php
  • Ceylon .ceylon

Note : experimental Nashorn support is included for js and coffee (requires Java 8). To use the Nashorn JS/Coffee engine rather than the default Rhino engine , then edit protocol_ta/bin/vertx_conf/


This is provisioned using your own Java Keystore that you can create using the keytool utility that is part of the JDK.

Refer to


Client certificate based authentication can be enabled for the TLS/SSL channels you setup.

VERTX Modules and Repositorys

Any required Vertx modules , such as various language modules for the polyglot functionality (JS , Scala , Groovy etc...) will be dynamically downloaded from online repositorys and installed in your protocol_ta/bin/vertx_modules directory.

You can edit your repository locations in protocol_ta/bin/vertx_conf/repos.txt

Performance tuning tips

Due to the nature of the async/event driven/non blocking architecture , the out of the box default settings may just well suffice for you.

But there are some other parameters that you can tune to take more advantage of your underlying computing resource(ie: cpu cores) available to you.

These are the "server_verticle_instances" and "handler_verticle_instances" params.

Refer to for an explanation of how increasing the number of instances may help you.

You can also tune the TCP accept queue settings (also requires OS tweaks) , particularly if you are receiving lots of connections within a short time span.

Refer to

Data Output

By default data will be output to STDOUT in Modular Input Stream XML format.

However you can bypass this if you wish and declare that data is output to a Splunk TCP port.


  • Splunk 5.0+
  • Java Runtime 1.7+
  • Supported on Windows, Linux, MacOS, Solaris, FreeBSD, HP-UX, AIX


  • Optionally set your JAVA_HOME environment variable to the root directory of your JRE installation.If you don't set this , the input will look for a default installed java executable on the path.
  • Untar the release to your $SPLUNK_HOME/etc/apps directory
  • Restart Splunk


As this is a Modular Input , you can then configure your Protocol inputs via Manager->Data Inputs->Protocol Data Inputs


Any log entries/errors will get written to $SPLUNK_HOME/var/log/splunk/splunkd.log

JVM Heap Size

The default heap maximum is 256MB.
If you require a larger heap, then you can alter this in $SPLUNK_HOME/etc/apps/protocol_ta/bin/ on line 95

JVM System Properties

You can declare custom JVM System Properties when setting up new input stanzas.
Note : these JVM System Properties will apply to the entire JVM context and all stanzas you have setup


  • JAVA_HOME environment variable is set or "java" is on the PATH for the user's environment you are running Splunk as
  • You are using Splunk 5+
  • You are using a 1.7+ Java Runtime
  • You are running on a supported operating system
  • Look for any errors in $SPLUNK_HOME/var/log/splunk/splunkd.log
  • Run this command as the same user that you are running Splunk as and observe console output : "$SPLUNK_HOME/bin/splunk cmd python ../etc/apps/protocol_ta/bin/ --scheme"


This project was initiated by Damien Dallimore ,

Release Notes

Version 1.3
Nov. 17, 2016

Added the latest jython jar to the main classpath because the jython language module that
is dynamically installed is missing some useful jython modules ie:json

Version 1.2
July 28, 2016

Added an example handler for decompressing gzip content

Version 1.1
Nov. 24, 2015

Minor HEC data handling tweaks

Version 1.0
Sept. 22, 2015

Added support to optional output to Splunk via a HEC (HTTP Event Collector) endpoint

Version 0.7
Feb. 11, 2015

Enabled TLS1.2 support by default.
Made the core Modular Input Framework compatible with latest Splunk Java SDK
Please use a Java Runtime version 7+
If you need to use SSLv3 , you can turn this on in bin/

Version 0.6
Nov. 15, 2014

Abstracted the output transport logic out into verticles.
So you can choose from STDOUT (default for Modular Inputs) or bypass this and output
data to Splunk over other transports ie: TCP.
This also makes it easy to add other output transports in the future.
Futhermore , this makes the implementation of custom data handlers much cleaner as you don't have
worry out output transport logic or formatting Modular Input Stream XML for STDOUT transports.

Version 0.5.1
Nov. 11, 2014

Added and repos.txt to the classpath

Version 0.5
Nov. 10, 2014

Initial beta release


Subscribe Share

Splunk Certification Program

Splunk's App Certification program uses a specific set of criteria to evaluate the level of quality, usability and security your app offers to its users. In addition, we evaluate the documentation and support you offer to your app's users.

Are you a developer?

As a Splunkbase app developer, you will have access to all Splunk development resources and receive a 50GB license to build an app that will help solve use cases for customers all over the world. Splunkbase has 1000+ apps and add-ons from Splunk, our partners and our community. Find an app or add-on for most any data source and user need, or simply create your own with help from our developer portal.

Follow Us:
© 2005-2018 Splunk Inc. All rights reserved.
Splunk®, Splunk>®, Listen to Your Data®, The Engine for Machine Data®, Hunk®, Splunk Cloud™, Splunk Light™, SPL™ and Splunk MINT™ are trademarks and registered trademarks of Splunk Inc. in the United States and other countries. All other brand names, product names, or trademarks belong to their respective owners.