Security

Blacklist events whose "Message" field contains a specific value "healthcheck" is not working.

aswinkumar6
New Member

I'm using a AWS setup with ELB sending constant healthcheck messages to my apache server. splunk is indexed to capture access logs. 37% of my access logs are captured with this unwanted healthcheck data. I wanted to blacklist this incoming data so I have added below configurations to splunkds inputs.conf.Below configuration is not working even after splunkds restart.

[monitor://]
blacklist1 = Response_code=200 && "healthcheck"

Please provide me solution on how the blacklisting of incoming traffic with response_code=200 and message="healthcheck" be configured.

Tags (1)
0 Karma

aswinkumar6
New Member

Hi Giuseppe,

As I'm using AWS setup, ELB is checking for server availablity and healthcheck logs are consuming more data.This is unwanted data .

I want do not want any incoming message with "ELB-HealthChecker/2.0" and Response_Code=200 in splunk indexes.

Below log message I want to filter

10.9x.xx.xx - - [31/May/2020:00:05:32 -0500] "GET /healthcheck HTTP/1.1" Response_Code=200 Bytes=26 "-" "ELB-HealthChecker/2.0" Response_Time=150

what is the correct regex and steps to do this?

0 Karma

gcusello
SplunkTrust
SplunkTrust

Hi @aswinkumar6,
blacklist in monitor stanzas (not in windos wineventlog stanzas) is related only to filenames not to events.

See my answer to your previous question https://answers.splunk.com/answers/824761/what-are-ways-to-optimize-splunk-license-usage.html .

As I said, you have to find the correct regex to filter your data (if you share some samples I cal help you) and then put on your indexers or (if present) on your Heavy Forwarders, the following files (this is an example of regex to define with your logs):

In props.conf:

[my_sourcetype]
TRANSFORMS-null= setnull

in transforms.conf:

[setnull]
REGEX = message\=healthcheck
DEST_KEY = queue
FORMAT = nullQueue

(if in the discarding events there the string message=healthcheck)

Ciao.
Giuseppe

0 Karma
Get Updates on the Splunk Community!

Splunk Observability for AI

Don’t miss out on an exciting Tech Talk on Splunk Observability for AI!Discover how Splunk’s agentic AI ...

Splunk Enterprise Security 8.x: The Essential Upgrade for Threat Detection, ...

Watch On Demand the Tech Talk on November 6 at 11AM PT, and empower your SOC to reach new heights! Duration: ...

Splunk Observability as Code: From Zero to Dashboard

For the details on what Self-Service Observability and Observability as Code is, we have some awesome content ...