merci pour la réponse.
c'est du RAID semi materiel.
premiere chose, j'ai tenté en supprimant la config RAID et en passant les disque en mode AHCI et l'install me propose bien les 4 disques .
j'ai remis ma config RAID, et la commande me retourne cela :
Error: /dev/sda: unrecognised disk label
Model: ATA ST2000DM001-1CH1 (scsi)
Disk /dev/sda: 2000GB
Sector size (logical/physical): 512B/4096B
Partition Table: unknown
Disk Flags:
Error: /dev/sdb: unrecognised disk label
Model: ATA ST2000DM001-1CH1 (scsi)
Disk /dev/sdb: 2000GB
Sector size (logical/physical): 512B/4096B
Partition Table: unknown
Disk Flags:
Error: /dev/sdc: unrecognised disk label
Model: ATA WDC WD20EZRX-00D (scsi)
Disk /dev/sdc: 2000GB
Sector size (logical/physical): 512B/4096B
Partition Table: unknown
Disk Flags:
Error: /dev/sdd: unrecognised disk label
Model: ATA WDC WD20EZRX-00D (scsi)
Disk /dev/sdd: 2000GB
Sector size (logical/physical): 512B/4096B
Partition Table: unknown
Disk Flags:
Model: USB 2.0 Flash Drive (scsi)
Disk /dev/sde: 8010MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 8009MB 8008MB primary fat32 boot, lba
Error: /dev/mapper/ddf1_4c53492020202020808627c3000000004711471100001450:
unrecognised disk label
Model: Linux device-mapper (striped) (dm)
Disk /dev/mapper/ddf1_4c53492020202020808627c3000000004711471100001450: 7996GB
Sector size (logical/physical): 512B/4096B
Partition Table: unknown
Disk Flags:
merci encore pour ton aide