For a Branch Gateway without an S8300 server or for a Branch Gateway with an S8300 server installed as an LSP, you can upgrade the Branch Gateway firmware from the remotely located primary controller. The primary controller may be an S8300 server. For more details about upgrading firmware from the primary controller, see Upgrading, Migrating, and Converting Avaya Servers and Gateways, 03-300412.
Note:
You can only upgrade using FTP on the S8300 server.