GDS functions which are available in the virtual environments (KVM and VMware) are as follows:
Purpose | Operating environment of GDS | Class | Description |
|---|---|---|---|
Mirroring a system disk on the host | Host (KVM) | Root class | Available in UEFI boot environment. The settings are the same with the conventional way where the virtual machine function is not used. |
Mirroring a system disk on the guest | Host (KVM) | Local class | Create a volume of a local class or a shared class on the host and install the guest OS there. |
Guest (VMware) | Root class | Available in UEFI boot environment. Mirroring of the following system disks, which were connected by the virtual SCSI controller, is available:
| |
Mirroring a virtual disk on the guest | Guests (KVM and VMware) | Local class | Supporting the mirroring in order to improve the availability. Mirroring of the following devices are available:
The settings are the same as the conventional way where the virtual machine function is not used. |
Management of the shared disk for the cluster system | Shared class | GDS manages the shared disk for the cluster system built between guests and enables the mirroring among servers. The following devices can be managed:
The settings are the same as the conventional way where the virtual machine function is not used. |
GDS: Global Disk Services
GDS Snapshot functions which are available in the virtual environments (KVM and VMware) are as follows:
Purpose | Operating environment of GDS Snapshot | Class | Description |
|---|---|---|---|
Snapshot of a system disk on the host Configuration of an Alternative Boot Environment on the host | Host (KVM) | Root class | Available in UEFI boot environment. The settings are the same with the conventional way where the virtual machine function is not used. |
Snapshot of data volume on the host | Host (KVM) | Local class | The settings are the same with the conventional way where the virtual machine function is not used. |
Snapshot of a system disk on the guest | Host (KVM) | Local class | Create a volume of a local class or a shared class on the host and install the guest OS there. Create a snapshot on the host. To ensure the consistency of snapshot data, you need to stop the guest OS during snapshot creation. |
Guest (VMware) | Root class | Available in UEFI boot environment. Available for the system disk of the following formats connected by the virtual SCSI controller:
| |
Configuration of an Alternative Boot Environment on the guest | Guest (VMware) | Root class | Available in the following environment:
Available for the system disk of the following formats connected by the virtual SCSI controller:
|
Snapshot of local volume on the guest | Host (KVM) | Local class | Create a local volume on the host and register it as a virtio block device on the guest OS. Create a snapshot on the host. |
Guests (KVM and VMware) | Local class |
| |
Snapshot of shared volume on the cluster system. | Guests (KVM and VMware) | Shared class |
|
GDS Snapshot: Global Disk Services Snapshot
Note
VMware vSAN
Virtual disk (VMDK) of VMware vSAN can be registered to the class.
However, it cannot be used for the mirroring among servers.
For the virtual disk redundancy of vSAN, perform either the mirroring function of GDS or redundant function of vSAN, and decide which function to use according to the system requirements.
For example, when constructing a system that does not make the administrator of the virtual machine aware of the redundant disk, the server administrator can construct such system by using the vSAN function to configure the redundant disk.
On the other hand, if you want to make the disk redundant to be used in the virtual machine in a cloud environment (except an FJcloud-Baremetal environment) where the disks are not made redundant by vSAN function, you can use the mirroring function of GDS on the virtual machine.
Note
When using GDS on both host and guest of KVM
For the disk used only on KVM guest, configure the following on the host.
Register the disk to the Excluded Device List of GDS.
For the Excluded Device List, see "6.1 Creating Excluded Device List."
Do not register the disk to the PRIMECLUSTER resource database.
For the resource registration, see "6.3 Shared Disk Resource Registration."
It is recommended to create different class names for the host and guest.
Information
How to copy the volumes created in a KVM guest by using the Advanced Copy function of ETERNUS
When using GDS Snapshot on the KVM guest, the Advanced Copy function of ETERNUS cannot be used.
To use the Advanced Copy function of ETERNUS, use ACM. For details, see the manual of ACM.
