Rapporto Tecnico, Anno 8, n° 44 settembre 2013

2.3 LVM
OS was installed using LVM partitioning as show here:
# fdisk -l /dev/sda
...
Device Boot
Start
/dev/sda1
*
2048
/dev/sda2
501758
/dev/sda5
501760

End
499711
156301311
156301311

Blocks
248832
77899777
77899776

Id
83
5
8e

System
Linux
Extended
Linux LVM

# pvdisplay
--- Physical volume --PV Name
/dev/sda5
VG Name
kvm2
PV Size
74.29 GiB / not usable 2.00 MiB
Allocatable
yes
PE Size
4.00 MiB
Total PE
19018
Free PE
14635
Allocated PE
4383
PV UUID
xxxxx
# lvdisplay
--- Logical volume --LV Name
/dev/kvm2/root
VG Name
kvm2
...
--- Logical volume --LV Name
/dev/kvm2/swap_1
VG Name
kvm2
...

We also use LVM for VM virtual disk. This architecture allows snapshots, flexible partition resize
and mixed local and remote storage.
After installed a first VM tubu1, LVM configuration will be:
# pvdisplay -m
--- Physical volume --PV Name
/dev/sda5
VG Name
kvm2
PV Size
74.29 GiB / not usable 2.00 MiB
...
--- Physical Segments --Physical extent 0 to 1359:
Logical volume
/dev/kvm2/root
Logical extents 0 to 1359
Physical extent 1360 to 2382:
Logical volume
/dev/kvm2/swap_1
Logical extents 0 to 1022
Physical extent 2383 to 4382:
Logical volume
/dev/kvm2/tubu1
Logical extents 0 to 1999
Physical extent 4383 to 19017:
FREE

2.4 iSCSI
Cluster remote storage is connected to KVM host by iSCSI protocol.
Install and configure iSCSI Initiator onto the KVM hypervisor:
# apt-get install open-iscsi
# nano -w /etc/iscsi/iscsid.conf
node.startup = automatic
# /etc/init.d/open-iscsi restart

8