4.9. Attaching and Configuring the Data Disk

# ssh username@instance_external_ip

# fdisk -l /dev/sdb

Disk /dev/sdb: 10984.4 GB, 10984378859520 bytes
255 heads, 63 sectors/track, 1335441 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00000000

#!/bin/bash
pvcreate /dev/sdb
vgcreate rhgs_vg /dev/sdb
# Create metadata LV with the maximum supported size of 16GB
lvcreate -L 16777216K --name rhgs_pool_meta rhgs_vg
# Create data LV with the remainder of the VG space
lvcreate -l 100%FREE --name rhgs_pool rhgs_vg
# The lvconvert command below required 4096 free extents, so reduce the LV
lvreduce -f -l 4096 /dev/rhgs_vg/rhgs_pool
# Convert our LVs to a thin pool
lvconvert --yes --thinpool rhgs_vg/rhgs_pool --poolmetadata rhgs_vg/rhgs_pool_meta
# Disable zeroing of thin pool chunks for performance boost
lvchange --zero n rhgs_vg/rhgs_pool
# The -V flag for lvcreate does not allow a ‘100%FREE’ option like -l does.
# So we’ll get the size of rhgs_pool from lvs for maximum efficiency
LVSIZE=$(lvs --units g | grep rhgs_pool | awk '{print $4}' | awk -F. '{print $1}')
# Create the thin LV for the bricks
lvcreate -V ${LVSIZE}G -T rhgs_vg/rhgs_pool -n rhgs_lv
# Create the XFS filesystem with 512B inode size and 8KB directory block size
# This step may take a while...
mkfs.xfs -f -i size=512 -n size=8192 -L rhgs_lv /dev/rhgs_vg/rhgs_lv
# Create mountpoint and fstab entry
mkdir -p /rhgs/bricks
echo "LABEL=rhgs_lv /rhgs/bricks xfs rw,inode64,noatime,nouuid 1 2" >> /etc/fstab
mount /rhgs/bricks
df -h /rhgs/bricks