Comprehensive and Detailed Explanation From Exact Extract:
The key requirement is to provide access to a private Git repository while keeping the SageMaker notebook instances isolated from the internet. The environment is intentionally configured without internet access, and connectivity to AWS services is provided through VPC endpoints. Introducing a NAT gateway and routing to the internet would violate the requirement to keep the notebook instances isolated from the internet, and network ACLs cannot reliably restrict outbound access by URL or domain name because NACLs operate at the IP and port level and do not provide DNS-aware URL filtering.
SageMaker supports integrating Git repositories so that notebooks can pull code directly as part of the workflow. When using a private repository, credentials must be handled securely. Using AWS Secrets Manager to store and reference Git credentials allows authentication without embedding usernames and passwords in code or URLs and without granting broad network access. This approach meets the requirement with low operational overhead because it relies on managed SageMaker Git integration and managed secret storage rather than custom networking controls.
Option A uses SageMaker’s Git repository integration with the remote URL and stores credentials in AWS Secrets Manager. This allows notebooks to access the private repository in a controlled, auditable way while preserving the “no internet access” posture of the VPC design (because it does not require adding a NAT gateway or public routes).
Option B is not appropriate because embedding credentials (even just usernames) in URLs is not a secure or robust credential management practice. It also does not solve private authentication in a secure manner and can lead to credential leakage through logs or configuration.
Options C and D are not correct because they require adding a NAT gateway and routing to the internet. That directly conflicts with the requirement that SageMaker notebook instances remain isolated from the internet. Additionally, the proposed restriction mechanism is invalid: network ACLs cannot restrict traffic to a specific URL. They only allow/deny traffic based on IP addresses, ports, and protocols. A Git repository can resolve to multiple IPs, can change IPs, and can use CDNs, making NACL-based IP allowlisting brittle and operationally heavy.
Therefore, integrating the Git repository with SageMaker and using Secrets Manager for credentials is the best solution with the least operational overhead while maintaining internet isolation.
[References:AWS documentation on SageMaker notebook Git repository integration for pulling code from remote repositories.AWS documentation on AWS Secrets Manager for secure storage and retrieval of credentials used by applications and workflows.AWS networking documentation describing that network ACLs operate on IP/port rules and do not support URL-based filtering, and that adding NAT gateway enables internet egress from private subnets., ]
