On Splunk Enterprise 9.0.4, we are using the Proofpoint Isolation TA to download Isolation data into Splunk from the Proofpoint Isolation cloud. However, when we activated SSL decryption on the URLs at our firewall for other necessary reasons, the TA stopped working, giving these errors in the logs:
2024-01-09 19:09:52,554 WARNING pid=9240 tid=MainThread file=connectionpool.py:urlopen:811 | Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1106)'))': /api/v2/reporting/usage-data?from=2023-11-29T01%3A17%3A33.000&to=2024-01-10T01%3A09%3A52.188&pageSize=10000
2024-01-09 19:09:52,657 ERROR pid=9240 tid=MainThread file=base_modinput.py:log_error:309 | Call to send_http_request failed: HTTPSConnectionPool(host='urlisolation.com', port=443): Max retries exceeded with url: /api/v2/reporting/usage-data?from=2023-11-29T01%3A17%3A33.000&to=2024-01-10T01%3A09%3A52.188&pageSize=10000 (Caused by SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1106)')))
The error makes sense, since it's not (yet) a "trusted root" cert for this Splunk instance.
How do I properly configure Splunk (or, perhaps, the Python client) to recognize this firewall root certificate as valid, or at the very least to stop validating the certificates provided by the outside server. The latter would be my least-preferred choice, obviously.