接第一篇《XIV（1）- Hardware Overview》讲述了XIV系统的大体的硬件组成，本篇继续讲XIV系统的Hardware Architecture。
1，Data Module/Interface Module
XIV Model A14 Data Module/Interface Module
Data Module和Interface Module的区别在于Interface Module有主机IO适配器和G网卡适配器，还有就是Data Module是一个Low voltage CPU而Interface有两个CPU。除了12个Disk之外，主要还有以下部件:
System Planar (motherboard)
Processor
Memory/cache
Enclosure Management Card
Cooling devices (fans)
Memory Flash Card [1 GB]--存储软件，Module配置文件及系统
Redundant power supplies
Gigabit Ethernet ports—ISCSI,FC
2，Power redundancy
有3个UPS，整套XIV可以运行在2个UPS上。
每个Module有2个单独的power supplies，正常情况下，两个power supplies都在最大workload的一半下运行。如果一个power supply坏掉，另一个power supply能接管过来，Module继续运行。
Automatic Transfer Switch (ATS)
ATS supplies power to all three UPSs and to the Maintenance Module. In case of a power problem on one line, the ATS reorganizes the power and switches to the other line. The operational components take over the load from the failing power source or power supply. This rearrangement is performed by the ATS in a seamless manner such that the system operation continues without any application impact.
Automatic Transfer Switch ATS
UPS
The UPS units work together to provide a “cache battery” function to sustain the IBM XIV Storage System in the event of power fluctuations or loss. 当掉电小于30s时，UPS能继续维持系统运行；当掉电过了30s后，UPS Module能维持Battery足够长的时间来安全有序地关机。
3，Maintenance module
用于维护机器，用于远程支持
参考书籍《SG24-7659-03，IBM XIV Storage System:Architecture, Implementation,and Usage》
