How do I obtain an SSL certificate for customers on partial (CNAME) setup? – Cloudflare Support

If your customers' domains were added on partial (CNAME) setup after July 20, 2017, you will need to use the following API call to obtain CNAME record/s for SSL to be issued successfully and placed under your authoritative DNS. Here is the API call:

curl -X GET "https://api.cloudflare.com/client/v4/zones/ZoneID/ssl/verification?retry=true" \
     -H "X-Auth-Email: [email protected]" \
     -H "X-Auth-Key: c2547eb745079dac9320b638f5e225cf483cc5cfdda41" \
     -H "Content-Type: application/json"

The output will be:

{
    "result": [
        {
            "certificate_status": "authorizing",
            "signature": "ECDSAWithSHA256",
            "brand_check": false,
            "verification_info": {
                "record_name": "_222222222222222222RRRRRRRR.example.com",
                "record_target": "24242424242424242424242424242424BBBBBBBBBBBBBBBBBBBB242424242424.comodoca.com"
            },
            "verification_status": null,
            "verification_type": "cname"
        }
    ],
    "success": true,
    "errors": [],
    "messages": []
}'

Please make sure you have a CNAME record specific to your domain in place to trigger obtaining the SSL certificate successfully (the example above is using fake values).

Cloudflare support