By default, jobs that are delegated or copied to a managed media server from the central administration server use the network and security settings that are set on the managed media server.
However, you can select an option on the central administration server to let a job use any network interface to access remote agents if the selected network interface is unavailable. Enabling this option for a backup job lets the managed media server use an alternative network interface to run important backup jobs that would otherwise fail to run.