这篇文章就简单介绍如何用软件实现raid技术（以raid0为例）。有两个可以实现软raid的工具：raidtools,mdadm。本文也以mdadm为例讲述。一、查看当前硬盘情况[root@primary/]#fdisk-lDisk/dev/sda:10.7GB,10737418240bytes255heads,63sectors/track,1305cylindersUnits=cylindersof16065*512=8225280bytesDeviceBootStartEndBlocksIdSystem/dev/sda1*11310439183Linux/dev/sda21411148843782+83Linux/dev/sda3111513051534207+82LinuxswapDisk/dev/sdb:107MB,107374080bytes64heads,32sectors/track,102cylindersUnits=cylindersof2048*512=1048576bytesDisk/dev/sdbdoesn'tcontainavalidpartitiontableDisk/dev/sdc:107MB,107374080bytes64heads,32sectors/track,102cylindersUnits=cylindersof2048*512=1048576bytesDisk/dev/sdcdoesn'tcontainavalidpartitiontable二、为硬盘分区raid一般多个硬盘来组成，你也可以用同一个硬盘的多个分区组成raid，但这样是没有意义的。[root@primary/]#fdisk/dev/sdbDevicecontainsneitheravalidDOSpartitiontable,norSun,SGIorOSFdisklabelBuildinganewDOSdisklabel.Changeswillremaininmemoryonly,untilyoudecidetowritethem.Afterthat,ofcourse,thepreviouscontentwon'tberecoverable.Warning:invalidflag0x0000ofpartitiontable4willbecorrectedbyw(rite)Command(mforhelp):nCommandactioneextendedpprimarypartition(1-4)pPartitionnumber(1-4):1Firstcylinder(1-102,default1):Usingdefaultvalue1Lastcylinderor+sizeor+sizeMor+sizeK(1-102,default102):Usingdefaultvalue102Command(mforhelp):wThepartitiontablehasbeenaltered!Callingioctl()tore-readpartitiontable.Syncingdisks.[root@primary/]#fdisk/dev/sdcDevicecontainsneitheravalidDOSpartitiontable,norSun,SGIorOSFdisklabelBuildinganewDOSdisklabel.Changeswillremaininmemoryonly,untilyoudecidetowritethem.Afterthat,ofcourse,thepreviouscontentwon'tberecoverable.Warning:invalidflag0x0000ofpartitiontable4willbecorrectedbyw(rite)Command(mforhelp):nCommandactioneextendedpprimarypartition(1-4)pPartitionnumber(1-4):1Firstcylinder(1-102,default1):Usingdefaultvalue1Lastcylinderor+sizeor+sizeMor+sizeK(1-102,default102):Usingdefaultvalue102Command(mforhelp):wThepartitiontablehasbeenaltered!Callingioctl()tore-readpartitiontable.Syncingdisks.此时硬盘的分区情况：[root@primary/]#fdisk-lDisk/dev/sda:10.7GB,10737418240bytes2