The distinction between mirroring and duplexing is that
with mirroring the two (or more) physical places where the data are written may be attached
to the same controller, leaving the storage still subject to the single point of
failure of the controller itself; in duplexing, two or more controllers are used. Mirroringand duplexing may occur on multiple storage devices that are physically at a distance
from one another, providing a degree of disaster tolerance.
with mirroring the two (or more) physical places where the data are written may be attached
to the same controller, leaving the storage still subject to the single point of
failure of the controller itself; in duplexing, two or more controllers are used. Mirroringand duplexing may occur on multiple storage devices that are physically at a distance
from one another, providing a degree of disaster tolerance.
1、镜像可能采用同一个控制器，存在单点故障
2、冗余备份可能采用两个或者多个控制器
