以前我有一个使用（ mdadm ）驱动器sda和sdb设置的软件raid。 sdb失败，重新启动系统的唯一方法是拔下第二个硬盘驱动器。
现在我已经添加了新的sdb和sdc到我的RAID设置。 sda是最老的（所以最有可能失败），这是我们开车的驱动器（我想，我怎么检查？）。
我如何确保和testing（通过GRUBconfiguration等），如果sda失败，我仍然可以启动我的机器。
fdisk -l ：
Disk /dev/sda: 250.0 GB, 250000000000 bytes 255 heads, 63 sectors/track, 30394 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000080 Device Boot Start End Blocks Id System /dev/sda1 * 1 30064 241489048+ fd Linux raid autodetect /dev/sda2 30065 30394 2650725 5 Extended /dev/sda5 30065 30394 2650693+ fd Linux raid autodetect Disk /dev/sdb: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sdb1 * 1 30064 241489048+ fd Linux raid autodetect Partition 1 does not start on physical sector boundary. /dev/sdb2 30065 30394 2650725 5 Extended /dev/sdb5 30065 30394 2650693+ fd Linux raid autodetect Partition 5 does not start on physical sector boundary. Disk /dev/sdc: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sdc1 * 1 30064 241489048+ fd Linux raid autodetect Partition 1 does not start on physical sector boundary. /dev/sdc2 30065 30394 2650725 5 Extended /dev/sdc5 30065 30394 2650693+ fd Linux raid autodetect Partition 5 does not start on physical sector boundary. Disk /dev/md0: 247.3 GB, 247284695040 bytes 2 heads, 4 sectors/track, 60372240 cylinders Units = cylinders of 8 * 512 = 4096 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Alignment offset: 512 bytes Disk identifier: 0x00000000 Disk /dev/md0 doesn't contain a valid partition table Disk /dev/md1: 2714 MB, 2714238976 bytes 2 heads, 4 sectors/track, 662656 cylinders Units = cylinders of 8 * 512 = 4096 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Alignment offset: 512 bytes Disk identifier: 0x00000000 Disk /dev/md1 doesn't contain a valid partition table
这是一个老栗子。 简短的回答是，“grub-install”通常是软件RAID的错误答案。 这里有一个例子，我有一个3路RAID-1arrays。 / boot分区存储在/ dev / md0。 这将GRUB安装到每个磁盘，以便如果一个磁盘发生故障，可以从其他磁盘启动。
# grub grub> find /grub/stage1 (hd0,0) (hd1,0) (hd2,0) grub> device (hd0) /dev/sda grub> root (hd0,0) grub> setup (hd0) grub> device (hd0) /dev/sdb grub> root (hd0,0) grub> setup (hd0) grub> device (hd0) /dev/sdc grub> root (hd0,0) grub> setup (hd0) grub> quit
在未来的GRUB版本中，它更聪明，但CentOS 6 / RHEL 6仍旧装载了旧的GRUB。
testing：将grub.conf文件（在/ boot下）的“timeout = 5”值改为timeout = 30。 然后在重新启动系统之前交换两个驱动器的位置。 或者更改BIOS中硬盘的启动顺序。
（当然，确保你有很好的备份，并知道如何恢复到正确的configuration。在一次性系统上testing这是一个好主意。）