# Page Not Found

The URL `2.21/start/requirements-and-prerequisites` does not exist.

You might be looking for one of these pages:
- [Requirements and prerequisites](https://docs.portainer.io/start/requirements-and-prerequisites.md)
- [Docker roles and permissions](https://docs.portainer.io/advanced/docker-roles-and-permissions.md)
- [UI and features](https://docs.portainer.io/faqs/troubleshooting/ui-and-features.md)
- [Certificates and security](https://docs.portainer.io/faqs/troubleshooting/certificates-and-security.md)
- [Which is more secure, the Agent or the Edge Agent?](https://docs.portainer.io/faqs/getting-started/which-is-more-secure-the-agent-or-the-edge-agent.md)

## How to find the correct page

1. **Browse the full index**: [/sitemap.md](https://docs.portainer.io/sitemap.md) - Complete documentation index
2. **View the full content**: [/llms-full.txt](https://docs.portainer.io/llms-full.txt) - Full content export

## Tips for requesting documentation

- For markdown responses, append `.md` to URLs (e.g., `/start/requirements-and-prerequisites.md`)
- Use `Accept: text/markdown` header for content negotiation