When testing Splunk Cloud, I'm getting an invalid certificate errors. Depending on which application I use, I may see...
"The remote certificate is invalid according to the validation procedure."
"Your connection isn't private
Attackers might be trying to steal your information from prd-p-dkgtr.splunkcloud.com (for example, passwords, messages, or credit cards).
Test URL: https://prd-p-dkgtr.splunkcloud.com:8088/
That's normal because your browser does not recognize the Certificate Authority used by Splunk Cloud. Just accept the warning and continue. If you cannot continue then try a different browser.
It's not just the browser, it's anything that needs to talk to the Splunk server. Which includes my applications that are trying to write to a log collector.