While there is ample documentation on certificate generation and application to both Splunk Web, Indexers, and Forwarders-- we often find that securing post-default deployment scenarios during PS engagements are no fun. We haven't had good luck with just 'pushing' certificates and having Universal Forwarders properly utilize them (at least in Windows environments). Utilizing the Deployment Server and pushing your own app and config packages still have clear text in many scenarios.
We would like to see a feature added for complete Web GUI of Splunk Certificate Management including:
Components: universal forwarders, indexers, and Splunk web server
Action/abilities for administrator user from within WebUI:
Import and use 3rd party signed CA certificates, and their respective keys (including mutual authentication client certs required)
Automated abilities Generate, replace/renew, and deploy certificates to all connecting forwarders (Windows and Linux)
Warning messages when certificates will expire
Enable a 'quick start' deployment default options of either using 3rd party signed certs or using self signed certs during installation for secure NOT JUST universal forwarder agent check in/control status messages but the actual data being forwarded from them. This also includes automatic proper TLS use ready for receiver
This doesn't read like you have a question, but I'll give you an answer... If you have a need for such a feature you should submit a P4 (Enhancement Request) ticket on your support entitlement, and/or talk to your account / partner teams about it. In order for anything to have a chance of being worked on by the development teams, it needs to get to Splunk's JIRA queues. While some employees may troll Splunk Answers, you have a better chance of getting it into their JIRA to be prioritized if it's logged through proper channels.