A remote, embedded loT server is having a Linux OS upgrade installed.

A microSD card is the best method to stage the new media for the default boot device of a remote embedded IoT server that is having a Linux OS upgrade installed. A microSD card is a small and portable storage device that can store large amounts of data. It can be easily inserted into the slot of an embedded IoT server, which is a small and low-power device that performs specific tasks and connects to other devices over a network. A microSD card can also be formatted with different file systems, such as FAT32 or ext4, which are compatible with Linux OS. References: CompTIA Server+ Certification Exam Objectives, Domain 4.0: Networking, Objective 4.3: Given a scenario, configure servers for IoT applications.