> For the complete documentation index, see [llms.txt](https://help.security.gallagher.com/knowledge-hub/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.security.gallagher.com/knowledge-hub/products/cloud-services/onelink/limitations-and-licensing.md). # Limitations and licensing Review OneLink functions, restrictions, deployment considerations, and licensing requirements. A OneLink controller has essentially all the functions of a normally LAN or WAN connected controller, **except** connecting to controllers outside its own local LAN for inter-controller communication. ## Not supported * **Inter-controller communications** with controllers that are **not** on the same local LAN. Cloud-connected controllers will not directly share alarm notifications and similar with remote peers. * **Downgrading to 9.20 or below** firmware. The controller will not communicate after downgrading. Command Centre will stop you from downgrading the controller if it is configured as a OneLink controller. ## Supported * Access Control * Alarms, local to the controller or to controllers on the same LAN * Inter-controller communications **on the same LAN** (TCP 1072) * Logic Blocks, local or same-LAN * Overrides from Command Centre, such as macros * Alarm transmission via IP or analog * Assigning a camera to an action plan * Updating credentials from a T20 reader (PIN enrolment) * Assigning background images to T20 readers * Controlled challenge * DESFire key rolling on cards * Software update of additional HBUS devices * Applying controller-specific customisations > ⚠️ **Random selection is unstable on OneLink.** Random selection, for example for screening or drug and alcohol testing, currently works but is **unstable**. Making it work correctly requires restarting the Command Centre services. This is being actively worked on. **Gallagher does not recommend using it on a OneLink controller at this stage.** ## Considerations * On a cellular connection, consider the controller's network traffic. For action plans on frequent but unimportant events, set the priority to **"not an event"** rather than **"Message Only"**. * Middleware is supported but **not recommended**, because of the network traffic it generates. This matters most over cellular. ## Licensing **No licence string is required.** * **End-user sites** must have a current SMA. At annual SMA renewal they are charged **per OneLink-configured controller**. * **Demo sites** are not charged at this stage. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://help.security.gallagher.com/knowledge-hub/products/cloud-services/onelink/limitations-and-licensing.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.