Azure spring application disconnects with storage account at specific time

Question

Azure spring application disconnects with storage account at specific time

Answer 1

Hello, thanks for reaching out on Microsoft Q&A and really appreciate your patience while we looked into this.

Before providing a definitive solution, it is critical to gather more information. Please help us with the following details:

1. Timing and Frequency: Does this disconnection happen every day at the same time, or is it a weekly or monthly event?
2. Authentication Method: How is the Azure Spring Apps instance authenticating with the storage account? Is it using Access Keys, a Managed Identity, or SAS tokens? (This is crucial, as SAS tokens have a configurable expiry time).
3. Networking Configuration: Is the Azure Spring Apps instance integrated into a Virtual Network? Are there any network restrictions on the storage account, such as firewall rules, private endpoints, or service endpoints?
4. Application Logs: What are the specific error messages from the application logs during the disconnection (e.g., 403 Forbidden, 401 Unauthorized, TimeoutException)?
5. Platform Events: Are there any scheduled platform events configured, such as auto-scaling rules, app restarts, or planned maintenance for the Azure Spring Apps instance?

Potential Solutions and Documentation

Based on the answers to the probing questions, the solution will likely fall into one of these categories:

1. If the issue is due to a SAS Token Expiration:
   • Problem: The application is using a Shared Access Signature (SAS) token that is set to expire at the specific time of the disconnection.
   • Solution: The most secure and recommended approach is to switch to a Managed Identity for authentication. This removes the need to manage secrets or keys and ensures a continuous, non-expiring connection.
   • Documentation: Use managed identities in Azure Spring Apps to access other resources
2. If the issue is a Network Configuration Problem:
   • Problem: The Spring Apps instance might be connecting via public IP, and a firewall rule is blocking the connection, or there's an issue with VNet integration.
   • Solution:
   • Option 1: Ensure that the outbound IP addresses of your Azure Spring Apps instance are correctly whitelisted in the Storage account's firewall.
   • Option 2 (Recommended): Use a Private Endpoint to establish a secure, private connection between the Spring Apps VNet and the Storage account. This bypasses the public internet and is more reliable.
   • Documentation:
   • Configure Azure Storage firewalls and virtual networks
3. If the issue is caused by Scheduled Platform Events:
   • Problem: The disconnection aligns with a scheduled app restart, a scaling event, or Azure platform maintenance.
   • Solution: Implement resilient design patterns and retry logic in your Spring application. This allows the application to gracefully handle transient network failures by automatically retrying the failed operation.
   • Documentation:
   • Resiliency in Azure Spring Apps
   • Working with Transient Errors in Azure SQL Database (applies to general retry logic)

Final Guidance

The most likely causes are either an expiring SAS token or a network-related restriction coinciding with a scheduled event. Once you provide the above details, we can help narrow down the exact cause. The long-term best practice is to leverage Managed Identity for authentication and use Private Endpoints for secure, stable connectivity.

I hope this helps. Please provide the additional information requested so we can guide you further. Thank-You!