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PREPARE.md

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Requirements

First we need to make sure we have all the appropriate tools.
Please consult this chart for help with installing the required packages.
If your OS is not listed, please help us fill out the table, or submit a request via github.

OS Commands (as root)
CentOS yum install -y epel-release; yum install -y calc dialog gdisk hdparm mdadm
Debian apt update; apt install --no-install-recommends -y apcalc btrfs-progs dialog gdisk hdparm mdadm
Fedora yum install -y btrfs-progs calc dialog gdisk hdparm mdadm
Ubuntu apt update; apt install apcalc btrfs-progs dialog gdisk hdparm mdadm

Disk Partitioning

In this example we will start with 8 blank disks.
Lets assume that we want to ignore disks sda and sdb.
We will modify disks /dev/sdc through /dev/sdj using /dev/sd[cdefghij]
Modify these locations to match your environment.
If you need to wipe a disk, you can use the command: sgdisk -Z <disk>
To prepare our disks, we will create a single partition on each disk.
The second command will ensure that the new partition has type code 8300.

for DISK in /dev/sd[cdefghij]; do sgdisk -n 1:0:0 ${DISK}; done
for DISK in /dev/sd[cdefghij]; do sgdisk -t 1:8300 ${DISK}; done

Filesystem Creation

Next we will put a btrfs filesystem on each new partition.
I chose btrfs because it supports checksumming of data blocks via the scrub command.
Scrubbing the disk regularly will allow us to prematurely identify issues that can be resolved.
NOTE: We will NOT be using the btrfs-raid feature, but just a generic btrfs filesystem on individual partitions.
We will assign a label to each filesystem that matches the serial number of the drive.
The last line of the for loop will create the map file. This will be used by other scripts.

for DISK in /dev/sd[cdefghij]; do
  PART="${DISK}1"
  LABEL=$(hdparm -I ${DISK} | grep 'Serial Number:' | awk '{print $3}')
  mkfs.btrfs -f -L ${LABEL} ${PART}
  mkdir -p /mnt/${LABEL}
  mount ${PART} /mnt/${LABEL} -t btrfs
  echo "/mnt/${LABEL}" >> mnt_locations.map
done

Disks, Partitions, and Labels

Assigning the FS labels that match serial numbers will allow us to easily group our disks by function.
Also, there is no guarantee that these disks will be given the same drive letter every time at startup.
Mounting drives by serial ensures we get the expected results upon every startup.
Use ls -l /dev/disk/by-label to see how the labels are mapped to your disks.

ls -l /dev/disk/by-label/
lrwxrwxrwx 1 root root 10 Apr 19 13:46 VAHJW81L -> ../../sdg1
lrwxrwxrwx 1 root root 10 Apr 19 13:46 VAHKY2ML -> ../../sdi1
lrwxrwxrwx 1 root root 10 Apr 19 13:46 VAHX5NWL -> ../../sdj1
lrwxrwxrwx 1 root root 10 Apr 19 13:46 VAJ0V17L -> ../../sdh1
lrwxrwxrwx 1 root root 10 Apr 19 13:46 VAJ7LEPL -> ../../sdc1
lrwxrwxrwx 1 root root 10 Apr 19 13:46 VAJBPNDL -> ../../sde1
lrwxrwxrwx 1 root root 10 Apr 19 13:46 VAJDDMHL -> ../../sdd1
lrwxrwxrwx 1 root root 10 Apr 19 13:46 VDG04BHK -> ../../sdf1

Using the mount command, we can see where all our newly created partitions got mounted.

mount                 

/dev/sdg1 on /mnt/VAHJW81L type btrfs (rw,nosuid,nodev,noatime,nodiratime)
/dev/sdi1 on /mnt/VAHKY2ML type btrfs (rw,nosuid,nodev,noatime,nodiratime)
/dev/sdj1 on /mnt/VAHX5NWL type btrfs (rw,nosuid,nodev,noatime,nodiratime)
/dev/sdh1 on /mnt/VAJ0V17L type btrfs (rw,nosuid,nodev,noatime,nodiratime)
/dev/sdc1 on /mnt/VAJ7LEPL type btrfs (rw,nosuid,nodev,noatime,nodiratime)
/dev/sde1 on /mnt/VAJBPNDL type btrfs (rw,nosuid,nodev,noatime,nodiratime)
/dev/sdd1 on /mnt/VAJDDMHL type btrfs (rw,nosuid,nodev,noatime,nodiratime)
/dev/sdf1 on /mnt/VDG04BHK type btrfs (rw,nosuid,nodev,noatime,nodiratime)

I use a script like this to ensure that my disks get mounted in the same place every startup.

for PART in /dev/disk/by-label/PV[ABCD]??????; do
  SERIAL=`basename ${PART}`
  mkdir -p /mnt/${SERIAL}
  mount ${PART} /mnt/${SERIAL} -t btrfs -o rw,nosuid,nodev,noatime,nodiratime
done