# Troubleshooting (/docs/sombra/deploying/troubleshooting)

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

### Cloudflare Proxy Limits [#cloudflare-proxy-limits]

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

### Using Proxy Servers with Sombra [#using-proxy-servers-with-sombra]

<Callout type="info">
  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.
</Callout>

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](https://nginx.org/en/docs/http/ngx_http_core_module.html#large_client_header_buffers)

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

### Using Egress Firewalls with Sombra [#using-egress-firewalls-with-sombra]

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.

### Additional Resources [#additional-resources]

If you encounter issues not covered in this guide, please contact Transcend Support or refer to the [Sombra deployment documentation](./index.mdx) for more detailed configuration instructions.