Troubleshooting

This guide provides recommendations for resolving common errors when deploying and configuring Sombra. Following these guidelines will help ensure a smooth deployment experience.

If you are using a proxy service like Cloudflare, ensure that you configure sufficiently large message size limits. Sombra may need to transfer files that are several gigabytes in size. We recommend:

  • Setting ingress and egress file size limits to at least 2 GiB
  • If a lower limit is required, 200 MiB should be sufficient for most use cases
  • Adjust these settings in your Cloudflare dashboard under Network → HTTP/HTTPS settings

This section is only relevant when using the Direct Connection method, as the Transcend Sombra Reverse Tunnel is a proxy service and does not require another proxy service in front of the Sombra containers.

If Sombra is hosted behind a proxy service like NGINX, certain Sombra requests may exceed the default limits imposed by the proxy, particularly for request header sizes.

For NGINX specifically:

  • Set the large_client_header_buffers configuration to at least 16k in your NGINX configuration
  • Example: large_client_header_buffers 4 16k;
  • Link to NGINX documentation

For other proxy services, look for similar settings that control maximum header size and request buffer limits.

Sombra communicates with the systems you connect in your Data Inventory. Since these integrations are added on an opt-in basis, customers using domain-based egress firewalls often face challenges maintaining up-to-date allowlists.

When implementing egress firewall controls:

  • Ensure you have robust monitoring to identify blocked connection attempts
  • Establish a streamlined process for updating allowed domains as you add new integrations
  • Consider allowing broader access initially during setup and testing phases
  • Implement more restrictive controls only after successfully connecting and validating several integrations
  • Maintain documentation of all required domains for your specific integration set

We recommend waiting to implement strict egress controls until after successfully testing Sombra with multiple integrations in your environment.

If you encounter issues not covered in this guide, please contact Transcend Support or refer to the Sombra deployment documentation for more detailed configuration instructions.