如何查看raid1整列

有一个服务器做了硬raid1，是linux的，linux下怎么查看我的raid1的这两块硬盘都是正常的，还是有一块硬盘坏掉了呢?现在查到只能用dmesg |grep -i raid
查看到是raid1

[root@localhost log]# dmesg |grep -i raid
megaraid cmm: 2.20.2.6 (Release Date: Mon Mar 7 00:01:03 EST 2005)
megaraid: 2.20.4.6 (Release Date: Mon Mar 07 12:27:22 EST 2005)
megaraid: probe new device 0x1000:0x1960:0x1000:0x0520: bus 4:slot 3:func 0
megaraid: fw version:[1L45] bios version:[G121]
scsi0 : LSI Logic MegaRAID driver
scsi[0]: scanning scsi channel 0 [Phy 0] for non-raid devices
Vendor: MegaRAID Model: LD 0 RAID1 420G Rev: 1L45
md: Autodetecting RAID arrays.
[root@localhost log]# cat /proc/scsi/scsi
Attached devices:
Host: scsi0 Channel: 01 Id: 00 Lun: 00
Vendor: MegaRAID Model: LD 0 RAID1 420G Rev: 1L45
Type: Direct-Access ANSI SCSI revision: 02
这里有没有显示两块硬盘都是好的？
如果没有有什么办法查出来？

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