AWS S3 Connection with Private Link

Hi All,

I am trying to establish a connection from Appian to AWS S3 bucket. I have created a connected system with and without DNS endpoint, please refer to the attached screenshots. It throws an error with endpoint URL.

With the endpoint URL error is: "Failed to parse XML document with handler class com.amazonaws.services.s3.model.transform.XmlResponsesSaxParser$ListAllMyBucketsHandler".

When I am using these connected systems in an integration object then it behaves as following:

• Integration object outcome without Endpoint URL in connected system: SUCCESS
  •  
• Integration object outcome with Endpoint URL in connected system: FAILED (Access Denied (Service: Amazon S3; Status Code: 403; Error Code: AccessDenied; Request ID: XXXXXXXXXXXXXXXX; S3 Extended Request ID: XXXXXXXXXXXXXXXX/yyyyyyyyyyyyyyyyyyy/ZZZZZZZZZZZZZZZ=; Proxy: null) Please review logs for stack trace.)
  • 

The AWS user used for connected system has the following policies:

• AmazonS3FullAccess
• AmazonVPCFullAccess
• Inline policy

  • {
      "Version": "2012-10-17",
      "Statement": [
        {
          "Effect": "Allow",
          "Action": [
            "s3:ListAllMyBuckets",
            "s3:ListBucket",
            "s3:PutObject",
            "s3:GetObject",
            "s3:DeleteObject"
          ],
          "Resource": [
            "arn:aws:s3:::bucketARN",
            "arn:aws:s3:::bucketARN/*"
          ],
          "Condition": {
            "StringEquals": {
              "aws:sourceVpce": "vpce-01cxxxxxxx"
            }
          }
        }
      ]
    }

Bucket permissions are as follows:

• Block all public access: ON
• Object Ownership: Bucket owner preferred
• Bucket policy

  • {
      "Version": "2012-10-17",
      "Statement": [
        {
          "Sid": "Statement1",
          "Effect": "Allow",
          "Principal": {
            "AWS": "arn:aws:iam::xxxxxx:user/arn"
          },
          "Action": [
            "s3:ListBucket",
            "s3:PutObject",
            "s3:GetObject"
          ],
          "Resource": [
            "arn:aws:s3:::bucketARN",
            "arn:aws:s3:::bucketARN/*"
          ],
          "Condition": {
            "StringEquals": {
              "aws:SourceVpce": "vpce-01cxxxxxxx"
            }
          }
        }
      ]
    }

Can anyone help me with the points I am missing here or if anyone has ever faced similar kind of issues?