Redundancy behavior

The Alnico redundant RAID storage subsystem implements ALAU (Asymmetric Logical Unit Access) algorithm which allows Volume Sets to be accessed by only one controller when both controllers are on-line. The controller, which controls the Volume Sets, is the preferred controller and another controller is for standby. For example, Volume Set #000 is controlled by controller 1, and the redundant RAID subsystem allows host server access Volume Set #000 only through controller 1. Controller 2 would take over the data I/O if controller 1 fails. The Alnico redundant RAID storage subsystem default assigns even Volume Sets to controller 1 and odd Volumes Sets to controller 2. For example, controller 1 is the preferred controller for Volume Set #000 and controller 2 is the preferred controller for Volume Set #001.

The Alnico redundant RAID storage subsystem is highly compatible with a variety of operating systems with their MPIO ( Windows Sever 2003, 2008, Vista and WIndows 7, Linux, Solaris &Mac O.S. ) and fully capable of coping with kinds of complicated applications ( VMware, XSAN2 and etc.).

The figure below shows a perspective into a general high availability failover cluster connection. In this example, there is always one redundant path beginning from the Alnico redundant RAID storage subsystem to the FC switch, and from the FC switch to the server in order to maintain normal data access between the server and storage in the event of a path failure or cut happening at any point ( Storage-> FC switch -> Server ) .

Throughput Performance

The demands for higher speeds and more system stability-oriented disk array have skyrocketed of late. To meet with the demand of that, the Alnico redundant RAID storage subsystem is employed with a very powerful I/O processor inside each controller. When the totally four paths are combined together, the maximum MB/Sec and IOP/Sec can easily reach over 1500MB/Sec and 120K IOP/Sec recorded on Intel “I/O Meter.”