Splunk TCP Connector

Configure the Splunk TCP connector to receive data from Splunk Universal Forwarders and Heavy Forwarders for AI-powered analysis of Splunk-instrumented infrastructure.

  8 minute read  

Overview

The Splunk TCP connector receives data from Splunk Universal Forwarders (UF) and Splunk Heavy Forwarders using the native Splunk TCP protocol. Splunk forwarders are widely deployed across enterprises to collect and forward logs, metrics, and events from servers, applications, and infrastructure. Content streams into Edge Delta Pipelines for analysis by AI teammates through the Edge Delta MCP connector.

The connector implements the Splunk forwarder protocol, accepting connections from Splunk forwarders and parsing Splunk metadata including index, sourcetype, source, host, and timestamps. Edge Delta acts as a Splunk indexer receiver, enabling Splunk-instrumented infrastructure to send data for AI-powered analysis without modifying forwarder configurations.

When you add this streaming connector, it appears as a Splunk TCP source in your selected pipeline. AI teammates access this data by querying the Edge Delta backend with the Edge Delta MCP connector.

Add the Splunk TCP Connector

To add the Splunk TCP connector, you configure Edge Delta to listen for incoming Splunk forwarder traffic, then update Splunk forwarders to send data to Edge Delta.

Prerequisites

Before configuring the connector, ensure you have:

  • Splunk Universal Forwarder or Heavy Forwarder configured and running
  • Network connectivity from Splunk forwarders to Edge Delta agents
  • Firewall rules allowing inbound TCP traffic on chosen port (9997 or 3421)
  • Administrative access to modify Splunk forwarder outputs.conf files

Configuration Steps

  1. Navigate to AI Team > Connectors in the Edge Delta application
  2. Find the Splunk TCP connector in Streaming Connectors
  3. Click the connector card
  4. Configure Listen address (default 0.0.0.0 for all interfaces)
  5. Set Port number (9997 for Splunk standard or 3421 custom)
  6. Configure Read Timeout (how long to wait for incoming data)
  7. Optionally configure Advanced Settings for TLS, rate limiting
  8. Select a target environment
  9. Click Save

The connector deploys and begins listening for Splunk forwarder connections.

Configure Splunk forwarders to send data to Edge Delta by editing $SPLUNK_HOME/etc/system/local/outputs.conf:

[tcpout]
defaultGroup = edgedelta

[tcpout:edgedelta]
server = edge-delta-host:9997
compressed = false

Restart Splunk forwarder after configuration:

$SPLUNK_HOME/bin/splunk restart
Splunk TCP connector configuration showing listen address, port, and TLS settings

Configuration Options

Connector Name

Name to identify this Splunk TCP connector instance.

Listen

IP address to bind to for listening.

Format: IPv4 address

Default: 0.0.0.0 (all interfaces)

Examples:

  • 0.0.0.0 - Listen on all network interfaces
  • 192.168.1.100 - Listen only on specific interface
  • 127.0.0.1 - Local host only (testing)

Port

TCP port to listen on for incoming Splunk forwarder traffic.

Format: Integer between 1 and 65535

Default: 3421

Examples:

  • 9997 - Splunk standard receiving port
  • 3421 - Edge Delta default port
  • 9998 - Alternative Splunk port

Note: Splunk forwarders typically use port 9997 by default

Read Timeout

How long to wait for incoming data before timing out connection.

Format: Duration (milliseconds, seconds, minutes)

Default: 1m

Examples:

  • 30s - 30 seconds for faster dead connection detection
  • 1m - 1 minute balanced timeout
  • 2m - 2 minutes for sparse event streams

Purpose: Prevents idle or disconnected forwarders from holding connections open

Advanced Settings

TLS

TLS settings enable encrypted HTTPS connections for secure Splunk forwarder traffic.

Configuration Options:

  • Ignore Certificate Check: Disables SSL/TLS certificate verification (use with caution)
  • CA File: Absolute file path to CA certificate for SSL/TLS
  • CA Path: Absolute path where CA certificate files are located
  • CRT File: Absolute path to SSL/TLS certificate file
  • Key File: Absolute path to private key file for SSL/TLS
  • Key Password: Optional password for private key file
  • Client Auth Type: Client authentication type (default: noclientcert)
  • Minimum Version: Minimum TLS version (default: TLSv1_2)
  • Maximum Version: Maximum TLS version

Client Auth Types:

  • noclientcert - No client certificate requested
  • requestclientcert - Client certificate requested but not required
  • requireanyclientcert - Client certificate required but not validated
  • verifyclientcertifgiven - Client certificate validated if provided
  • requireandverifyclientcert - Client certificate required and validated

TLS Versions: TLSv1_0, TLSv1_1, TLSv1_2, TLSv1_3

When to Use: Enable for production environments with sensitive log data

Splunk forwarder TLS configuration (outputs.conf):

[tcpout:edgedelta]
server = edge-delta-host:9997
sslCertPath = $SPLUNK_HOME/etc/auth/server.pem
sslPassword = password
sslVerifyServerCert = false

Metadata Level (Resource Attributes)

This option is used to define which detected resources and attributes to add to each data item as it is ingested by Edge Delta. You can select:

  • Required Only: This option includes the minimum required resources and attributes for Edge Delta to operate.
  • Default: This option includes the required resources and attributes plus those selected by Edge Delta
  • High: This option includes the required resources and attributes along with a larger selection of common optional fields.
  • Custom: With this option selected, you can choose which attributes and resources to include. The required fields are selected by default and can’t be unchecked.

Based on your selection in the GUI, the source_metadata YAML is populated as two dictionaries (resource_attributes and attributes) with Boolean values.

See Choose Data Item Metadata for more information on selecting metadata.

Splunk TCP-specific metadata included:

  • Host name - Edge Delta agent hostname
  • Host IP - Edge Delta agent IP address
  • Service name - Service identifier
  • Source name - Connector instance name
  • Source type - Splunk TCP connector type

Splunk metadata extracted from events:

  • Splunk index - Target Splunk index name
  • Splunk sourcetype - Data type classification
  • Splunk source - Original source path or identifier
  • Splunk host - Originating host of data
  • Event timestamp - Original event timestamp

Metadata Level (Attributes)

Additional attribute-level metadata fields to include.

Default: ed.env.id

Rate Limit

Rate limit configuration to control volume of Splunk data accepted.

Purpose: Protects Edge Delta from being overwhelmed by excessive forwarder volumes

Configuration:

  • Evaluation Policy: Policy to decide whether source will be rate limited

When to Use: Prevent high-volume forwarders from overwhelming the pipeline

How to Use the Splunk TCP Connector

The Splunk TCP connector integrates seamlessly with AI Team, enabling data ingestion from Splunk-instrumented infrastructure. AI teammates automatically leverage Splunk-forwarded data to analyze application logs, investigate security events, monitor infrastructure health, and track error patterns across Splunk indexes.

Use Case: Application Log Analysis

Analyze application logs from Splunk Universal Forwarders monitoring application servers. AI teammates identify error patterns, detect anomalies, and correlate issues across multiple servers without manually searching Splunk indexes. This is valuable for troubleshooting application failures, identifying recurring errors, and understanding application behavior.

Configuration:

  • Listen: 0.0.0.0
  • Port: 9997
  • Read Timeout: 1m

Splunk forwarder (outputs.conf):

[tcpout]
defaultGroup = edgedelta

[tcpout:edgedelta]
server = edge-delta-host:9997
compressed = false

Use Case: Security Event Monitoring

Monitor security logs from Splunk Heavy Forwarders with TLS encryption. AI teammates analyze authentication failures, detect brute force attacks, and identify security anomalies across infrastructure. Using TLS ensures sensitive security data is encrypted during transmission.

Configuration:

  • Listen: 0.0.0.0
  • Port: 9997
  • Read Timeout: 2m
  • TLS: Enabled

Splunk forwarder (outputs.conf):

[tcpout]
defaultGroup = edgedelta
forwardedindex.filter.disable = true

[tcpout:edgedelta]
server = edge-delta-host:9997
sendCookedData = true
sslCertPath = $SPLUNK_HOME/etc/auth/server.pem
sslVerifyServerCert = false

Use Case: Multi-Index Cross-Analysis

Analyze data across multiple Splunk indexes (main, security, application, metrics) for cross-index insights. AI teammates provide correlation analysis, track event volume by index, identify top hosts per index, and detect ingestion anomalies. This enables unified analysis across Splunk’s data silos.

Configuration:

  • Listen: 0.0.0.0
  • Port: 9997
  • Read Timeout: 1m

Troubleshooting

Connection refused errors: Verify Edge Delta listening on port with netstat -tuln | grep 9997. Test connectivity from forwarder with telnet edge-delta-host 9997. Check firewall rules allow TCP traffic on configured port. Review Splunk forwarder logs at $SPLUNK_HOME/var/log/splunk/splunkd.log for connection errors.

Forwarder connects but no data appears: Verify outputs.conf correctly points to Edge Delta host and port in [tcpout:edgedelta] section. Check Splunk forwarder running with $SPLUNK_HOME/bin/splunk status. Verify forwarder queue status with splunk list forward-server. Check Edge Delta agent running and healthy.

TLS handshake failures: Verify TLS enabled on both Splunk forwarder (outputs.conf with SSL settings) and Edge Delta connector. Check certificate and private key valid and matching. Ensure forwarder trusts Edge Delta certificate. Review sslVerifyServerCert setting in forwarder config. Check SSL errors in both forwarder and Edge Delta logs.

Missing Splunk metadata fields: Verify metadata level configuration includes Splunk index, sourcetype, source, and host extraction. Check Splunk forwarder sending properly formatted events. Review event structure in Edge Delta pipeline logs. Some Splunk field extractions happen at indexer level and won’t occur when forwarding to Edge Delta.

Excessive connection churn: Check forwarder reconnection loops in Splunk logs. Verify read timeout not too short for event rate. Monitor forwarder queue status for event buildup. Review Edge Delta resource usage (CPU, memory, file descriptors). Consider increasing timeout or load balancing across multiple Edge Delta agents.

Slow throughput or delayed events: Check network bandwidth between forwarders and Edge Delta. Review forwarder queue configuration in outputs.conf (maxQueueSize, compression). Enable compression in forwarder to reduce bandwidth. Monitor CPU and memory on both forwarders and Edge Delta agents. Deploy multiple Edge Delta agents with load balancing for high volumes.

Configuration changes not applied: Remember connector config in Edge Delta controls where agents listen, but Splunk forwarders must be explicitly reconfigured. After changing connector, update outputs.conf on each forwarder and restart Splunk service. Verify new config active with splunk list forward-server. Update firewall rules for new ports or TLS settings.

Next Steps

For additional help, visit AI Team Support.