hardware raid or software raid ?
Soft raid
what is the output of
cat /proc/mdstat
[root@mail ~]# cat /proc/mdstat
Personalities : [raid1]
md9 : active raid1 sdc2[3] sda2[2]
204736 blocks super 1.0 [2/2] [UU]
bitmap: 0/1 pages [0KB], 65536KB chunk
md0 : active raid1 sda1[2] sdc1[3]
510976 blocks super 1.2 [2/2] [UU]
bitmap: 0/1 pages [0KB], 65536KB chunk
md1 : active raid1 sda3[2] sdc3[3]
1952664576 blocks super 1.2 [2/2] [UU]
bitmap: 7/15 pages [28KB], 65536KB chunk
unused devices: <none>
also
lsblk
[root@mail ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 1,8T 0 disk
├─sda1 8:1 0 500M 0 part
│ └─md0 9:0 0 499M 0 raid1 /boot
├─sda2 8:2 0 200M 0 part
│ └─md9 9:9 0 200M 0 raid1 /boot/efi
└─sda3 8:3 0 1,8T 0 part
└─md1 9:1 0 1,8T 0 raid1
├─main-root 253:0 0 1,8T 0 lvm /
└─main-swap 253:1 0 7,8G 0 lvm [SWAP]
sdb 8:16 0 1,8T 0 disk
├─sdb1 8:17 0 500M 0 part
├─sdb2 8:18 0 200M 0 part
└─sdb3 8:19 0 1,8T 0 part
sdc 8:32 0 1,8T 0 disk
├─sdc1 8:33 0 500M 0 part
│ └─md0 9:0 0 499M 0 raid1 /boot
├─sdc2 8:34 0 200M 0 part
│ └─md9 9:9 0 200M 0 raid1 /boot/efi
└─sdc3 8:35 0 1,8T 0 part
└─md1 9:1 0 1,8T 0 raid1
├─main-root 253:0 0 1,8T 0 lvm /
└─main-swap 253:1 0 7,8G 0 lvm [SWAP]
sdd 8:48 0 1,8T 0 disk
└─sdd1 8:49 0 16M 0 part
and
file -s /dev/sda
file -s /dev/sdb
file -s /dev/sdc
[root@mail ~]# file -s /dev/sda
/dev/sda: x86 boot sector; partition 1: ID=0xee, starthead 0, startsector 1, 3907029167 sectors, extended partition table (last)\011, code offset 0x0
[root@mail ~]# file -s /dev/sdb
/dev/sdb: x86 boot sector; partition 1: ID=0xee, starthead 0, startsector 1, 3907029167 sectors, extended partition table (last)\011, code offset 0x0
[root@mail ~]# file -s /dev/sdc
/dev/sdc: x86 boot sector; partition 1: ID=0xee, starthead 0, startsector 1, 3907029167 sectors, extended partition table (last)\011, code offset 0x0