SSL Certificate Verification Error with MCP Integration to OpenSearch

OpenSearch
1

Hi everyone! I’m trying to set up an MCP (Model Context Protocol) integration with Claude to connect to my OpenSearch cluster, but I’m running into SSL certificate issues.Setup:

  • Configured MCP server to connect Claude to OpenSearch cluster
  • OpenSearch running on internal IP: my-ip:31580 (exposed from a kubernetes cluster via a NodePort)
  • MCP integration working, but SSL verification failing

Error:

ConnectionError: HTTPSConnectionPool(host='10.113.61.83', port=31580): Max retries exceeded with url: /_cat/indices?format=json (Caused by SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1028)')))

Questions:

  1. What’s the proper way to configure SSL settings for MCP connections to OpenSearch?
  2. Should I disable SSL verification in the MCP server config for internal clusters?
  3. Any specific OpenSearch SSL configuration recommendations for MCP integrations?
  4. Has anyone successfully set up MCP with self-signed certificates?

The MCP server itself is running fine - it’s specifically the SSL handshake with OpenSearch that’s failing. Any guidance on the SSL configuration would be super helpful!
Thanks!

2

@cristid9 I got similar setup working with OpenAI by passing the root-ca from opensearch. In my case using python script that uses the root-ca to verify the connection. Using self-signed CA. Have you tried to configure this?