HDD disks not showing

[masterp2020]

Hello guys,
Working on a DELL Poweredge T430 running CentOS7 server. I have 6 HDD disks of 300 GB each in the machine but only one is showing. I want to create RAID 5 with all the disks for the server to be used as a NAS storage. Kindly help how to be able to make the disks available on my centos 7 server.

That's the output of the command: fdisk -l

Disk /dev/sda: 299.4 GB, 299439751168 bytes, 584843264 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000beaf4

Device Boot Start End Blocks Id System
/dev/sda1 * 2048 2099199 1048576 83 Linux
/dev/sda2 2099200 584843263 291372032 8e Linux LVM

Disk /dev/mapper/cl-root: 53.7 GB, 53687091200 bytes, 104857600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/mapper/cl-swap: 8321 MB, 8321499136 bytes, 16252928 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/mapper/cl-home: 236.3 GB, 236349030400 bytes, 461619200 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Thanks

[TrevorH]

What sort of controller are the disks attached to? If it's PERC Sxxx then it's FakeRAID and you need to go into the controller BIOS and set it to AHCI mode, not RAID, then do the install and create a linux software RAID array instead.

[tunk]

And if it's not FakeRAID you still need to enter the controller BIOS and setup the hardware RAID.