lsblk give me 2x of the number of drive connected to my device.

Photo of hardware

The box on the top only have 3 hdd, one is completely empty. it's in raid 1 and cent7 is installed in there. The box at the bottom is the storage, they are connected via some controller shown in the picture. The box at the bottom have 16x 300GB hdd.

 [root@zircon ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 279.5G 0 disk sdb 8:16 0 279.5G 0 disk sdc 8:32 0 279.5G 0 disk sdd 8:48 0 279.5G 0 disk sde 8:64 0 279.5G 0 disk sdf 8:80 0 279.5G 0 disk sdg 8:96 0 279.5G 0 disk sdh 8:112 0 279.5G 0 disk sdi 8:128 0 279.5G 0 disk sdj 8:144 0 279.5G 0 disk sdk 8:160 0 279.5G 0 disk sdl 8:176 0 279.5G 0 disk sdm 8:192 0 279.5G 0 disk sdn 8:208 0 279.5G 0 disk sdo 8:224 0 279.5G 0 disk sdp 8:240 0 279.5G 0 disk sdq 65:0 0 279.5G 0 disk sdr 65:16 0 279.5G 0 disk sds 65:32 0 279.5G 0 disk sdt 65:48 0 279.5G 0 disk sdu 65:64 0 279.5G 0 disk sdv 65:80 0 279.5G 0 disk sdw 65:96 0 279.5G 0 disk sdx 65:112 0 279.5G 0 disk sdy 65:128 0 279.5G 0 disk sdz 65:144 0 279.5G 0 disk sr0 11:0 1 1024M 0 rom sdaa 65:160 0 279.5G 0 disk sdab 65:176 0 279.5G 0 disk sdac 65:192 0 279.5G 0 disk sdad 65:208 0 279.5G 0 disk sdae 65:224 0 279.5G 0 disk sdaf 65:240 0 279.5G 0 disk sdag 66:0 0 74.5G 0 disk └─md126 9:126 0 74.5G 0 raid1 ├─md126p1 259:0 0 500M 0 md /boot └─md126p2 259:1 0 74G 0 md ├─centos-root 253:0 0 44.7G 0 lvm / ├─centos-swap 253:1 0 7.5G 0 lvm [SWAP] └─centos-home 253:2 0 21.8G 0 lvm /home sdah 66:16 0 74.5G 0 disk └─md126 9:126 0 74.5G 0 raid1 ├─md126p1 259:0 0 500M 0 md /boot └─md126p2 259:1 0 74G 0 md ├─centos-root 253:0 0 44.7G 0 lvm / ├─centos-swap 253:1 0 7.5G 0 lvm [SWAP] └─centos-home 253:2 0 21.8G 0 lvm /home 

What I am confused here is, when I do lsblk, I get 32 (16x2) of 300gb of sd*. Why? I expect 16.

*new discovery

[root@zircon /]# mount /dev/sdi /data mount: unknown filesystem type 'zfs_member' 

It seems those sd* are zfs which is not readable by linux. So I guess I have to reformat it?