CloudStack支持多种流行的Hypervisor,你可以在所有的主机上使用一种,也可以使用不同的Hypervisor,但在同一个群集内的主机必须使用相同的Hypervisor。
你可能已经安装并运行了特定的hypervisor节点,在这种情况下,你的Hypervisor选择已经确定了。如果还处于初步规划阶段,那么就需要决定那种Hypervisor能切合你的需求。各种Hypervisor的利弊讨论不在本文档之列。但无论如何,CloudStack可以支持每种Hypervisor的那些功能的详细信息还是能够帮到你的。下面的表格就提供了这些信息:
Hypervisor Support for Primary Storage
The following table shows storage options and parameters for different
hypervisors.
Primary Storage Type |
XenServer |
vSphere |
KVM - RHEL |
LXC |
HyperV |
Format for Disks, Templates,
and Snapshots |
VHD |
VMDK |
QCOW2 |
|
VHD |
iSCSI support |
CLVM |
VMFS |
Yes via Shared
Mountpoint |
Yes via Shared
Mountpoint |
否 |
Fiber Channel support |
Yes, Via
existing SR |
VMFS |
Yes via Shared
Mountpoint |
Yes via Shared
Mountpoint |
否 |
NFS support |
是 |
是 |
是 |
是 |
否 |
Local storage support |
是 |
是 |
是 |
是 |
是 |
Storage over-provisioning |
NFS |
NFS and iSCSI |
NFS |
|
否 |
SMB/CIFS |
否 |
否 |
否 |
否 |
是 |
XenServer uses a clustered LVM system to store VM images on iSCSI and
Fiber Channel volumes and does not support over-provisioning in the
hypervisor. The storage server itself, however, can support
thin-provisioning. As a result the CloudStack can still support storage
over-provisioning by running on thin-provisioned storage volumes.
KVM supports “Shared Mountpoint” storage. A shared mountpoint is a file
system path local to each server in a given cluster. The path must be
the same across all Hosts in the cluster, for example /mnt/primary1.
This shared mountpoint is assumed to be a clustered filesystem such as
OCFS2. In this case the CloudStack does not attempt to mount or unmount
the storage as is done with NFS. The CloudStack requires that the
administrator insure that the storage is available
With NFS storage, CloudStack manages the overprovisioning. In this case
the global configuration parameter storage.overprovisioning.factor
controls the degree of overprovisioning. This is independent of
hypervisor type.
Local storage is an option for primary storage for vSphere, XenServer,
and KVM. When the local disk option is enabled, a local disk storage
pool is automatically created on each host. To use local storage for the
System Virtual Machines (such as the Virtual Router), set
system.vm.use.local.storage to true in global configuration.
CloudStack supports multiple primary storage pools in a Cluster. For
example, you could provision 2 NFS servers in primary storage. Or you
could provision 1 iSCSI LUN initially and then add a second iSCSI LUN
when the first approaches capacity.