| `HD_BASE_URL` | - | `https://md.example.com` | The URL the HedgeDoc instance is accessed with, like it is entered in the browser |
| `HD_BACKEND_PORT` | 3000 | | The port the backend process listens on. |
| `HD_FRONTEND_PORT` | 3001 | | The port the frontend process listens on. |
| `HD_RENDERER_BASE_URL` | Content of HD_BASE_URL | | The URL the renderer runs on. If omitted this will be the same as `HD_BASE_URL`. For more detail see [this faq entry][faq-entry] |
| `HD_INTERNAL_API_URL` | Content of HD_BASE_URL | `http://localhost:3000` | This URL is used by the frontend to access the backend directly if it can't reach the backend using the `HD_BASE_URL` |
| `HD_SHOW_LOG_TIMESTAMP` | true | | Specifies if a timestamp should be added to the log statements. Disabling is useful for extern log management (systemd etc.) |
| `HD_FORBIDDEN_NOTE_IDS` | - | `notAllowed,alsoNotAllowed` | A list of note ids (separated by `,`), that are not allowed to be created or requested by anyone. |
| `HD_MAX_DOCUMENT_LENGTH` | 100000 | | The maximum length of any one document. Changes to this will impact performance for your users. |
| `HD_PERSIST_INTERVAL` | 10 | `0`, `5`, `10`, `20` | The time interval in **minutes** for the periodic note revision creation during realtime editing. `0` deactivates the periodic note revision creation. |
