AccessDenied error on s3a:// bucket due to Serverless Network Policy in Databricks SQL Endpoint

[jeremylllin]

I wrote this code in Notebook

files = dbutils.fs.ls("s3a://testbuket114/")

for f in files:

print(f.name)

it caused err

s3a://testbuket114/: getFileStatus on s3a://testbuket114/: com.amazonaws.services.s3.model.AmazonS3Exception: Access to storage destination is denied because of serverless network policy; request: GET http://testbuket114.s3.us-east-1.amazonaws.com {key=[], key=[false], key=[2], key=[2], key=[/]} Hadoop 3.3.6, aws-sdk-java/1.12.638 Linux/5.15.0-1072-aws OpenJDK_64-Bit_Server_VM/17.0.13+11-LTS java/17.0.13 scala/2.12.15 kotlin/1.9.10 vendor/Azul_Systems,_Inc. cfg/retry-mode/legacy com.amazonaws.services.s3.model.ListObjectsV2Request; Request ID: null, Extended Request ID: null, Cloud Provider: AWS, Instance ID: unknown credentials-provider: com.amazonaws.auth.BasicSessionCredentials credential-header: AWS4-HMAC-SHA256 Credential=ASIA2OAJT3OJXLJL4HDN/20250620/us-east-1/s3/aws4_request signature-present: true (Service: Amazon S3; Status Code: 403; Error Code: AccessDenied; Request ID: null; S3 Extended Request ID: null; Proxy: 192.168.200.20), S3 Extended Request ID: null:AccessDenied SQLSTATE: 42501

err in sql query

INTERNAL: [UNAUTHORIZED_ACCESS] Unauthorized access: s3a://testbuket114/: getFileStatus on s3a://testbuket114/: com.amazonaws.services.s3.model.AmazonS3Exception: Access to storage destination is denied because of serverless network policy; request: GET http://testbuket114.s3.us-east-1.amazonaws.com {key=[], key=[false], key=[2], key=[2], key=[/]} Hadoop 3.3.6, aws-sdk-java/1.12.638 Linux/5.15.0-1072-aws OpenJDK_64-Bit_Server_VM/17.0.13+11-LTS java/17.0.13 scala/2.12.15 kotlin/1.9.10 vendor/Azul_Systems,_Inc. cfg/retry-mode/legacy com.amazonaws.services.s3.model.ListObjectsV2Request; Request ID: null, Extended Request ID: null, Cloud Provider: AWS, Instance ID: unknown credentials-provider: com.amazonaws.auth.BasicSessionCredentials credential-header: AWS4-HMAC-SHA256 Credential=REDACTED_ACCESS_KEY(da3c912f)/20250620/us-east-1/s3/aws4_request signature-present: true (Service: Amazon S3; Status Code: 403; Error Code: AccessDenied; Request ID: null; S3 Extended Request ID: null; Proxy: 192.168.200.20), S3 Extended Request ID: null:AccessDenied SQLSTATE: 42501

I already create external location in catalog

and credential 

Despite all this, I still get the same error with no Request ID or Extended Request ID.

Has anyone encountered this issue or have suggestions on what else I should check or configure? Could there be caching or propagation delays in the Serverless Network Policy? Or any other hidden settings that might block access?

Thanks in advance for your help!

[Isi]

Hello @jeremylllin ,

From the error message:
Access to storage destination is denied because of serverless network policy

Databricks serverless environments require explicit network access policies to reach AWS resources like S3. Even if you’ve already configured credentials and external locations, these policies act as an extra layer of protection.

Check your account Network policies(Serverless) in the admin console under Cloud resources > Network > Network policies (Serverless):

 Check if you have "Allow access to all destinations"

If that doesn't solve your problems check this Serverless Network Access Control for AWS 

This page explains how to configure private connectivity from Serverless compute to your in-region AWS S3 buckets using the Databricks account console UI.

A dedicated and private connection: Ensures secure and isolated access between your serverless workspaces and AWS S3, limiting access to authorized connections only.

Hope this helps, 🙂

Isi