ERROR TcpOutputProc - Processing server from outputs.conf: can't resolve a valid IP address for host

Applicability

Splunk Enterprise Splunk Cloud Splunk Universal Forwarder

Description

Following errors being observed:

ERROR TcpOutputProc - Processing server from outputs.conf: can't resolve a valid IP address for host=Now skipping indexing of internal audit events, because the downstream queue is not accepting data. Will keep dropping events until data flow resumes. Review system health: ensure downstream indexing and/or forwarding are operating correctly.The TCP output processor has paused the data flow. Forwarding to host_dest= inside output group default-autolb-group from host_src= has been blocked for blocked_seconds=. This can stall the data flow towards indexing and other network outputs. Review the receiving system's health in the Splunk Monitoring Console. It is probably not accepting data. Learn more.

Investigation

If this is a standalone/single instance make sure Splunk does not have any configuration on the outputs.conf under the server setting with the same IP address as their current standalone, as this is not needed and might cause issues with data/queues getting blocked and will cause Splunk cycling back and forward blocking all other queues and having indexing issues with anything that wants to get into Splunk.

This can also be due to network issues on the forwarder side - more details on ERROR TcpOutputProc - Processing server from outputs.conf: can't resolve a valid IP address for host="xxxx.xxx.xxx" DNS troubleshooting guide

Resolution

1. Verify the server setting in the outputs.conf to make sure it is not configured with the same IP as the instance.
2. If this is a single instance, there is no need to have the outputs.conf configured to forward data. This setting can be removed from the following stanza:

[tcpout:<group_name]
server = splunk.com:9997

3. Restart Splunk service.

Revision History

Revision	Publish Date	Comments
1.0	29-Sep-2026	Initial Release