Как создавали СХД для СВ NumaTech
mdadm lvm numatech bcache
1) Create soft RAID
# mdadm create --verbose /dev/md0 --level=10 --raid-devices 6 /dev/sdb /dev/sdc ... /dev/sdg
# cat /proc/mdstat
2) Add cache device bcache
# modinfo bcache
# rpm -Uhv bcache-utils-xxxxx.rpm
Make md0 as backing device
# make-bcache -B /dev/md0
Make sdh as cache device
# make-bcache -C /dev/sdh
# make-bcache --block 4k --bucket 2M -C /dev/sdh
find its cache set UUID,
# bcache-super-show /dev/sdh | grep cset.uuid
# echo cset.uuid > /sys/block/bcache0/bcache/attach
Set cache policy for bcache (writeback - faster, writetrue - safety)
# echo writeback > /sys/block/bcache0/bcache/cache_mode
# mkinitcpio -p linux
3) Add volumes
# modprobe raid1
# modprobe raid5
# modprobe raid10
# modprobe dm-mod
# vgcreate data /dev/bcache0
# vgdisplay
# lvcreate -L 100G data -n iscsi_slice
4) Create filesystem
# mkfs.ext4 /dev/data/p0
5) update initramfs
# dracut -d bcache --force