how to verify number of disks in RAID but from OS

we have Linux RHEL server - 7.6 version in server disks are : lsblk -S NAME HCTL TYPE VENDOR MODEL REV TRAN sda 0:2:0:0 disk DELL PERC FD33xD 4.27 sdb 1:0:0:0 disk ATA INTEL SSDSC1BG40 DL2B sata sdc 2:0:0:0 disk ATA INTEL SSDSC1BG40 DL2B sata sdc and sdb are the OS disks about sda is disk that represented by RAID so sda include number of disks , but the question is how to count the number of disks in RAID we tried the following but we not sure if this cli described the number of disks in RAID? smartctl --scan /dev/sda -d scsi # /dev/sda, SCSI device /dev/sdb -d scsi # /dev/sdb, SCSI device /dev/sdc -d scsi # /dev/sdc, SCSI device /dev/bus/0 -d megaraid,0 # /dev/bus/0 [megaraid_disk_00], SCSI device /dev/bus/0 -d megaraid,1 # /dev/bus/0 [megaraid_disk_01], SCSI device /dev/bus/0 -d megaraid,2 # /dev/bus/0 [megaraid_disk_02], SCSI device /dev/bus/0 -d megaraid,3 # /dev/bus/0 [megaraid_disk_03], SCSI device /dev/bus/0 -d megaraid,4 # /dev/bus/0 [megaraid_disk_04], SCSI device /dev/bus/0 -d megaraid,5 # /dev/bus/0 [megaraid_disk_05], SCSI device /dev/bus/0 -d megaraid,6 # /dev/bus/0 [megaraid_disk_06], SCSI device /dev/bus/0 -d megaraid,7 # /dev/bus/0 [megaraid_disk_07], SCSI device /dev/bus/0 -d megaraid,8 # /dev/bus/0 [megaraid_disk_08], SCSI device /dev/bus/0 -d megaraid,9 # /dev/bus/0 [megaraid_disk_09], SCSI device /dev/bus/0 -d megaraid,10 # /dev/bus/0 [megaraid_disk_10], SCSI device /dev/bus/0 -d megaraid,11 # /dev/bus/0 [megaraid_disk_11], SCSI device /dev/bus/0 -d megaraid,12 # /dev/bus/0 [megaraid_disk_12], SCSI device /dev/bus/0 -d megaraid,13 # /dev/bus/0 [megaraid_disk_13], SCSI device /dev/bus/0 -d megaraid,14 # /dev/bus/0 [megaraid_disk_14], SCSI device /dev/bus/0 -d megaraid,15 # /dev/bus/0 [megaraid_disk_15], SCSI device lspci -vv | grep -i raid 06:00.0 RAID bus controller: LSI Logic / Symbios Logic MegaRAID SAS-3 3108 [Invader] (rev 02) Kernel driver in use: megaraid_sas mdadm --detail /dev/sda mdadm: /dev/sda does not appear to be an md device cat /proc/mdstat Personalities : [raid1] md1 : active raid1 sdb2 sdc2 390054912 blocks super 1.2 [2/2] [UU] bitmap: 2/3 pages [8KB], 65536KB chunk md0 : active raid1 sdb1 sdc1 524224 blocks super 1.0 [2/2] [UU] bitmap: 0/1 pages [0KB], 65536KB chunk unused devices: lsscsi [0:2:0:0] disk DELL PERC FD33xD 4.27 /dev/sda [1:0:0:0] disk ATA INTEL SSDSC1BG40 DL2B /dev/sdb [2:0:0:0] disk ATA INTEL SSDSC1BG40 DL2B /dev/sdc cat /proc/partitions major minor #blocks name 8 0 13670809600 sda 8 16 390711384 sdb 8 17 524288 sdb1 8 18 390185984 sdb2 8 32 390711384 sdc 8 33 524288 sdc1 8 34 390185984 sdc2 9 0 524224 md0 9 1 390054912 md1 253 0 104857600 dm-0 253 1 16777216 dm-1 253 2 104857600 dm-2 253 3 10485760 dm-3 ll /sys/block/ total 0 lrwxrwxrwx 1 root root 0 Oct 17 07:27 dm-0 -> ../devices/virtual/block/dm-0 lrwxrwxrwx 1 root root 0 Oct 17 07:27 dm-1 -> ../devices/virtual/block/dm-1 lrwxrwxrwx 1 root root 0 Oct 17 07:27 dm-2 -> ../devices/virtual/block/dm-2 lrwxrwxrwx 1 root root 0 Oct 17 07:27 dm-3 -> ../devices/virtual/block/dm-3 lrwxrwxrwx 1 root root 0 Oct 17 07:27 md0 -> ../devices/virtual/block/md0 lrwxrwxrwx 1 root root 0 Oct 17 07:27 md1 -> ../devices/virtual/block/md1 lrwxrwxrwx 1 root root 0 Oct 17 07:27 sda -> ../devices/pci0000:00/0000:00:03.0/0000:02:00.0/0000:03:01.0/0000:04:00.0/0000:05:01.0/0000:06:00.0/host0/target0:2:0/0:2:0:0/block/sda lrwxrwxrwx 1 root root 0 Oct 17 07:27 sdb -> ../devices/pci0000:00/0000:00:11.4/ata1/host1/target1:0:0/1:0:0:0/block/sdb lrwxrwxrwx 1 root root 0 Oct 17 07:27 sdc -> ../devices/pci0000:00/0000:00:11.4/ata2/host2/target2:0:0/2:0:0:0/block/sdc ll /sys/block/ |grep 'primary' no output