Migrating Workflows to Azure with the WF Azure Activity Pack

Troubleshooting Common Issues in the WF Azure Activity Pack

1. Installation and Package Issues

• Symptom: NuGet package not found or install fails.
  • Fix: Ensure your project targets a supported .NET framework version required by the activity pack. Clear NuGet caches (dotnet nuget locals all –clear) and restore packages. Confirm package source (nuget.org) is enabled.

2. Assembly Binding and Version Conflicts

• Symptom: FileLoadException or type mismatch at runtime.
  • Fix: Check assembly versions referenced in your project and in the activity pack’s dependencies. Use binding redirects in app.config/web.config for .NET Framework projects, or consolidate package versions via the project file / NuGet centrally managed versions for SDK-style projects.

3. Authentication and Credential Failures

• Symptom: Authentication errors when activities call Azure services.
  • Fix: Verify credentials (managed identity, service principal, or connection string) are correct and have required permissions. For Managed Identity, ensure the host (App Service, VM, Function) has identity enabled and role assignments are granted. For service principals, confirm client secret/certificate validity and tenant ID.

4. Connectivity and Network Errors

• Symptom: Timeouts or network unreachable exceptions connecting to Azure endpoints.
  • Fix: Check outbound network rules, firewall, NSG, and proxy settings. Ensure DNS resolution works from the host. For private endpoints or VNet-restricted services, confirm appropriate private link or VNet integration is configured.

5. Serialization and Input/Output Mismatches

• Symptom: Activity fails with serialization errors or unexpected null/empty inputs.
  • Fix: Validate input arguments and ensure they match expected types. If using complex types, confirm they are serializable or use known types. Add null checks and default values in workflows.

6. Throttling and Rate Limits

• Symptom: 429 responses or transient failures under load.
  • Fix: Implement retry policies with exponential backoff. Use activity retry options where supported, or wrap calls with resilient libraries (e.g., Polly). Respect Azure service quotas and consider request batching.

7. Timeout and Long-Running Operations

• Symptom: Workflow activities time out before Azure operation completes.
  • Fix: Increase activity timeout settings or use asynchronous patterns: start operation, persist state, and poll or use callbacks for completion. Ensure persistence provider for Workflow Foundation is configured correctly if using durable persistence.

8. Logging and Diagnostics

• Symptom: Hard to identify root cause due to sparse logs.
  • Fix: Enable detailed logging and diagnostics. Capture activity input/output, exceptions, and correlation IDs. Integrate with Application Insights or other logging sinks. Use Azure portal activity logs for service-side errors.

9. Compatibility with Azure SDK Changes

• Symptom: Breaking changes after updating Azure SDK packages.
  • Fix: Lock compatible package versions or update activity pack to a version that supports the newer SDK. Review release notes for breaking changes and adapt code accordingly.

10. Deployment and Environment Differences

• Symptom: Works locally but fails in production.
  • Fix: Compare environment settings: app settings, connection strings, identity, network, and package versions. Reproduce production configuration locally or use staging slots. Ensure secrets are correctly provisioned in production secret store.

Quick Troubleshooting Checklist

1. Verify package versions and assembly bindings.
2. Confirm authentication method and permissions.
3. Test network connectivity and DNS.
4. Validate input types and serialization.
5. Enable detailed logging and collect correlation IDs.
6. Implement retries for transient faults.
7. Compare local and production environment configurations.

If you want, I can provide sample retry code, binding-redirect examples, or a checklist tailored to your host type (App Service, Function, VM).