General log forwarding via Fluentd

Deliver raw logs from files to S3 using Fluentd

Overview

Consider using Fluent Bit instead of Fluentd to forward logs to Panther. Fluent Bit is easier to set up and less resource intensive than Fluentd.

This is a guide for delivering raw logs from files to Panther via S3 and Fluentd. The Fluentd configurations below do not pre-process the data, instead they forward the contents of the file(s) as-is. This guide will walk you through how to do the following:

• Install Fluentd on your device.

• Edit your Fluentd configuration via an AWS Firehose or an S3 plugin.

• Launch and verify your Fluentd instance is running correctly.

Prerequisites

An S3 bucket or AWS Firehose is required. If you need to create either of these resources, please see the Fluentd Onboarding Guide. You can also adapt the guide below to fit your needs if you already have the resources provisioned.

Setup Fluentd to deliver raw logs to Panther

Step 1: Install Fluentd

Follow the Fluentd install guide for the server environment you want to collect syslog messages from. Once installed, you may proceed with the terminal configurations below to properly configure Fluentd.

Step 2: Edit Fluentd Configuration

You have two options when configuring Fluentd – Firehouse plugin or S3 plugin. We recommend the Firehose plugin option, as it is the more performant option with Panther. However, both will deliver your logs to S3.

Two different authentication types are shown in the configuration – assume roles or access keys. Use the authentication type that best suits your environment.

Be aware of the below plugin configurations with Fluentd:

• The <source> section uses the tail plugin to read from a log file.

• The <parse> section instructs the Fluentd to not perform any parsing with @type none.

• Within the match format section, the single_value type is used.

• The combination of none parsing and single_value format tells Fluentd to output the data as-is.

Configuration 1: Via Firehose Plugin (recommended)

The Firehose plugin for Fluentd must be installed to leverage the @type kinesis plugin.

1. Install the following Fluentd plugin with the command below.

   td-agent-gem install fluent-plugin-kinesis

2. Edit the Fluentd configuration located at /etc/td-agent/td-agent.conf with the configuration below. Make sure to update the region, delivery_stream_name, and role_arn:

   <source>  
     @type tail
     tag syslog
     path /path/to/file/*.log
     pos_file /var/log/td-agent/pos_file.pos
     <parse>
       @type none
     </parse>
   </source>
   
   <match syslog.**>
     @type kinesis_firehose
     region <FIREHOSE-REGION>
     delivery_stream_name <FIREHOSE-NAME>
   
     <assume_role_credentials>
       duration_seconds 3600
       role_arn <FIREHOSE-ROLE-ARN>
       role_session_name "#{Socket.gethostname}-panther-audit"
     </assume_role_credentials>
     <format>
       @type single_value
     </format>
   </match>

Configuration 2: Via S3 Plugin

1. Edit the Fluentd configuration located at /etc/td-agent/td-agent.conf, with the configuration below. Make sure to update the s3_bucket, s3_region, aws_key_id, and aws_sec_key:

   <source>  
     @type tail
     tag syslog
     path /path/to/file/*.log
     pos_file /var/log/td-agent/pos_file.pos
     <parse>
       @type none
     </parse>
   </source>
   
   <match syslog.**>
     @type s3
     aws_key_id <ACCESS-KEY-ID>
     aws_sec_key <SECRET-KEY>
     s3_bucket <BUCKET-NAME>
     s3_region <BUCKET-REGION>
     path syslog/%Y/%m/%d/
     store_as gzip
     <buffer tag,time>
       @type file
       path /var/log/td-agent/buffer/s3
       timekey 300 # 5 min partition
       timekey_wait 2m
       timekey_use_utc true # use utc
       chunk_limit_size 256m
     </buffer>
     <format>
       @type single_value
     </format>
   </match>

Step 3: Start Fluentd

1. After configuring Fluentd, run the below command in your terminal:

   $ sudo systemctl start td-agent.service 

2. To verify that Fluentd is running correctly, run the below command in your terminal:

   $ sudo systemctl status td-agent.service

If systemctl is not available in your Fluentd environment, see the Fluentd install guide.