# Setting the MAVLink REST Server Parameters In the default configuration, the Tracker 650 sends odometry information to the autopilot on a BlueROV via an interface on the BlueROV called the MAVLink Rest Server. There are several configuration parameters, all of which are set to reasonable parameters at the factory. Most users can leave these at the default settings. See also [this discussion](/c/tracker-650/using-mavlink-and-blueos-for-position-hold-on-a-bluerov2.md). The **MAVLink Server Address and Port** parameters set the IP address of the MAVLink server, which on a BlueROV is the IP address of the BlueROV itself. By default it is 192.168.2.2:6040. If you have changed the BlueROV address you need to re-enter it here. The port number is virtually always 6040. The **MAVLink System ID** identifies the Tracker 650 itself and is used by the MAVLink server to sort out who is talking to it. You only need to change this if you have a complicated network with other similar systems talking to the MAVLink server, and there is a collision with the system ID used by another device. The **MAVLink Vehicle ID** identifies the autopilot associated with the BlueROV you are trying to control. You should know if you changed the ID on the BlueROV and what you set it to. One situation where you might have to change your BlueROV vehicle ID is if you have other BlueBoats and/or BlueROVs on the same subnet. The **checkbox to send the global origin** is tricky. If you have a small basic system with just a BlueROV and Tracker 650, checking this box will cause a global origin of (0,0) to be send when everyone powers up. This will enable the BlueROV to use the Tracker 650 for position hold and dead reckoning. The downside is, the BlueROV thinks it is located off the west coast of Africa and the map on QGroundControl won't be correct. But, this does get position hold working for a basic user. If you know how to set a global origin by other means (e.g., CeruleanTracker, SonarView, an Omnitrack system), you definitely do NOT want this box checked. For arcane reasons, the autopilot accepts only one global origin per power cycle, so once set to (0,0) you are stuck with it until you reboot the ROV. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.ceruleansonar.com/c/tracker-650/configuring-the-tracker-650/setting-the-mavlink-rest-server-parameters.md?ask= ``` The question should be specific, self-contained, and written in natural language. 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.