https://slackware.absolutehosting.net/pub/slackware/slackware64-current/README_RAID.TXT


iroot@slackware:~# fdisk -l /dev/sda
Disk /dev/sda: 6 GiB, 6442450944 bytes, 12582912 sectors
Disk model: VBOX HARDDISK   
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xb3a6ba41

Device     Boot    Start      End  Sectors  Size Id Type
/dev/sda1           2048   411647   409600  200M fd Linux raid autodetect
/dev/sda2         411648 10897407 10485760    5G fd Linux raid autodetect
/dev/sda3       10897408 12228607  1331200  650M fd Linux raid autodetect



sfdisk -d /dev/sda | sfdisk --Linux /dev/sdb
sfdisk -d /dev/sda | sfdisk --Linux /dev/sdc



mdadm --create /dev/md0 --level 1 --raid-devices 3  /dev/sda1 /dev/sdb1 /dev/sdc1 --metadata=0.90
mdadm --create /dev/md1 --level 5 --raid-devices 3  /dev/sda2 /dev/sdb2 /dev/sdc2
mdadm --create /dev/md2 --level 1 --raid-devices 3  /dev/sda3 /dev/sdb3 /dev/sdc3 --metadata=0.90

root@slackware:~# cat /proc/mdstat 
Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] [multipath] 
md2 : active raid1 sdc3[2] sdb3[1] sda3[0]
      665536 blocks [3/3] [UUU]
      
md1 : active raid5 sdc2[3] sdb2[1] sda2[0]
      10475520 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/3] [UUU]
      
md0 : active raid1 sdc1[2] sdb1[1] sda1[0]
      204736 blocks [3/3] [UUU]
      
unused devices: <none>




let's redo all of that, since I botched it probably

# root
mdadm --create /dev/md0 --name=0 --level 5 --raid-devices 3 /dev/sda2 /dev/sdb2 /dev/sdc2

# swap
mdadm --create /dev/md1 --name=1 --level 1 --raid-devices 3 /dev/sda3 /dev/sdb3 /dev/sdc3

# boot
mdadm --create /dev/md2 --name=2 --level 1 --raid-devices 3 /dev/sda1 /dev/sdb1 /dev/sdc1 --metadata=0.90



# grr... again?

# lst's go for RAID1 first

mdadm --create /dev/md0 --level 1 --raid-devices 3 /dev/sda1 /dev/sdb1 /dev/sdc1 --metadata=0.90
mdadm --create /dev/md1 --name=1 --level 1 --raid-devices 3 /dev/sda2 /dev/sdb2 /dev/sdc2

mkswap /dev/md1

mdadm -Es > /etc/mdadm.conf

edit /etc/lilo.conf
raid-extra-boot = mbr-only
boot = /dev/md0



OK< that worked!

now let's try RAID5 again

root@slackware:~# fdisk /dev/sda -l
Device     Boot    Start      End  Sectors  Size Id Type
/dev/sda1           2048   206847   204800  100M fd Linux raid autodetect
/dev/sda2         206848 14886911 14680064    7G fd Linux raid autodetect
/dev/sda3       14886912 16320511  1433600  700M fd Linux raid autodetect

mdadm --create /dev/md0 --name=0 --level 5 --raid-devices 3 /dev/sda2 /dev/sdb2 /dev/sdc2
mdadm --create /dev/md1 --name=1 --level 1 --raid-devices 3 /dev/sda3 /dev/sdb3 /dev/sdc3
mdadm --create /dev/md2 --name=2 --level 1 --raid-devices 3 /dev/sda1 /dev/sdb1 /dev/sdc1 --metadata=0.90

mkswap /dev/md1

root@slackware:/# grep -v '#' /etc/lilo.conf
append="root=/dev/md0 "
raid-extra-boot = mbr-only
boot = /dev/md2