A Photon server is an appliance that provides hardware accelerated storage-over-network to the Sunlight nodes.
The Photon chassis consists of two tightly coupled Sunlight Storage Acceleration Units (SSAU), each one capable of handling 4x NVMe on board disks (a total of eight (8x) NVMe disks per Photon chassis). Each SSAU of the Photon chassis can be connected directly to a Sunlight cluster via an optical 100G Ethernet link.
Apart from the high-speed 100G Ethernet uplink, each SSAU offers an extra 1Gbps physical interface for management traffic. This interface is directly attached to the Processing System (PS) and could be used for the initial chassis configuration and/or for future on-premise maintenance.
The software and firmware images for each SSAU are stored in an internal QSPI (EEPROM) chip.
Photon chassis installation
For the initial Photon chassis programming , a SD memory card is used from the factory, in order to flash the Sunlight software and firmware images in an internal special purpose memory chip QSPI (EEPROM) of each SSAU. This card can also be used from the on-premise side, applying hard QSPI reset to factory settings of the Photon appliance.