Dot Hill Systems II 200 FC service manual 1.2.2 I/O Expansion Modules, Disk Drives

Specific Integrated Circuit (ASIC) controller chips handle the interconnection between the controller bus, DRAM memory, and Peripheral Component Interconnect (PCI) internal buses. They also handle the interface between the on-board 2-Mbyte flash memory, 32-Kbyte nonvolatile random access memory (NVRAM), RS-232 port chip, and 10/100 BASE-T Ethernet chip.

The RAID I/O controller module is a multifunction board. I/O controller modules include Small Form-Factor Pluggable (SFP) ports, SCSI Enclosure Services (SES) logic, and the RAID controller. The SES logic monitors various temperature thresholds, fan speed from each fan, voltage status from each power supply, and the

FRU ID.

Each RAID I/O controller module incorporates SES direct-attached Fibre Channel capability to monitor and maintain enclosure environmental information. The SES controller chip monitors all internal +12 and +5 voltages, various temperature sensors located throughout the chassis, and each fan. The SES also controls the front-panel and back-panel LEDs and the audible alarm. Both the RAID chassis and the expansion chassis support dual SES failover capabilities for fully redundant event monitoring.

1.2.2I/O Expansion Modules

The hot-serviceable I/O expansion modules provide four (SANnet II 200 FC array) or eight (SANnet II 200 SATA array), or six (SANnet II 200 SATA SE array) SFP ports but do not have battery modules or controllers. I/O expansion modules are used with I/O controller modules in non-redundant FC arrays, SATA arrays, and SATA SE arrays and in expansion units and JBODs.

You can connect SANnet II 200 SATA expansion units to SANnet II 200 FC arrays. However, certain restrictions and limitations apply to mixed Fibre Channel and SATA environments.

1.2.3Disk Drives

Each disk drive is mounted in its own sled assembly. Each sled assembly has electromagnetic interference (EMI) shielding, an insertion and locking mechanism, and a compression spring for maximum shock and vibration protection.

Each disk drive is slot independent, meaning that once a logical drive has been initialized, the system can be shut down and the drives can be removed and replaced in any order. In addition, disk drives are field upgradeable to larger drives without interruption of service to user applications. The drive firmware is also field upgradeable, but the firmware upgrade procedure requires interruption of service.

Chapter 1 Product and Architecture Overview 1-9