Quick and dirty.
Add disk.
Use the SCSI rediscovery trick if you can’t reboot the machine:
Check on which host the new drive is located:
# grep mpt /sys/class/scsi_host/host?/proc_name
/sys/class/scsi_host/host2/proc_name:mptspi
# echo "- - -" > /sys/class/scsi_host/host2/scan
http://www.golinuxhub.com/2014/07/how-to-detect-new-hard-disk-attached.html
# fdisk -l
# fdisk /dev/sdb
n
p
1
enter
enter
t
8e
w
# pvcreate /dev/sdb1
# vgextend VM_Name /dev/sdb1
# lvcreate -s -n snapshot -L 10G /dev/VM_Name/root
# mkdir /mnt/snapshot
# mount -o ro /dev/VM_Name/snapshot /mnt/snapshot
Do stuff if you screw up.
# umount /mnt/snapshot
# lvremove /dev/VM_Name/snapshot
# pvmove /dev/sdb1
# vgreduce VM_Name /dev/sdb1