Kinesis Firehose源记录访问拒绝且S3输出桶为空问题求助

Hey Dan, let's work through this Kinesis Firehose issue you're facing—since your app can send records to Firehose (we see that from the IncomingBytes/Records metrics) but nothing's hitting S3, the problem is almost definitely with Firehose's permissions to write to your bucket. Here's how to troubleshoot step by step:

Firehose uses its own dedicated IAM role to deliver data to S3—this is separate from the credentials your .NET app uses. Let's verify this role has all the necessary access:

• Ensure the role includes these permissions in its policy (replace placeholders with your bucket details):

  {
    "Version": "2012-10-17",
    "Statement": [
      {
        "Effect": "Allow",
        "Action": [
          "s3:PutObject",
          "s3:AbortMultipartUpload"
        ],
        "Resource": "arn:aws:s3:::your-target-bucket/*"
      },
      {
        "Effect": "Allow",
        "Action": "s3:ListBucket",
        "Resource": "arn:aws:s3:::your-target-bucket"
      }
    ]
  }
  

• Confirm the role's trust policy allows Firehose to assume it:

  {
    "Version": "2012-10-17",
    "Statement": [
      {
        "Effect": "Allow",
        "Principal": {
          "Service": "firehose.amazonaws.com"
        },
        "Action": "sts:AssumeRole"
      }
    ]
  }
  

Even if the Firehose role has the right permissions, your bucket's policy might be blocking access:

• Look for any Deny statements that could be overriding allow permissions (common if you have strict bucket security settings).
• Add an explicit allow statement for the Firehose role if it's missing:

  {
    "Version": "2012-10-17",
    "Statement": [
      {
        "Effect": "Allow",
        "Principal": {
          "AWS": "arn:aws:iam::your-account-id:role/your-firehose-execution-role"
        },
        "Action": [
          "s3:PutObject",
          "s3:AbortMultipartUpload",
          "s3:ListBucket"
        ],
        "Resource": [
          "arn:aws:s3:::your-target-bucket",
          "arn:aws:s3:::your-target-bucket/*"
        ]
      }
    ]
  }
  

• Also, make sure your bucket's Block Public Access settings aren't interfering—Firehose uses IAM-based access, so these should be fine as long as you're not relying on public access.

Firehose logs detailed error messages to CloudWatch, which will tell you exactly what's failing:

• Go to the CloudWatch Console, navigate to Logs > Log Groups, and look for the group named /aws/kinesisfirehose/your-stream-name.
• Open the latest log streams—you'll likely see an AccessDenied error with specifics, like missing S3 permissions, KMS key access issues, or bucket policy conflicts.

If your S3 bucket uses server-side encryption with KMS (SSE-KMS), the Firehose role needs additional permissions:

• Add these KMS actions to the role's policy (replace with your KMS key ARN):

  {
    "Effect": "Allow",
    "Action": [
      "kms:GenerateDataKey",
      "kms:Decrypt"
    ],
    "Resource": "arn:aws:kms:your-region:your-account-id:key/your-key-id"
  }
  

• Also, update your KMS key's policy to allow the Firehose role to access it.

Since your .NET app can successfully interact with other AWS services (EC2, SimpleDB, S3), we can rule out general credential issues. The fix will almost certainly be in the Firehose role's permissions or the S3 bucket's configuration. Start with checking the CloudWatch logs first—they'll give you the fastest path to the root cause!

内容的提问来源于stack exchange，提问作者Dan Csharpster