NUP Virtual Datacenter

Introduction

A Virtual Datacenter (vDC) is a set of resources including:

• computing power, expressed in GHz or vCPU, and quantity of RAM,
• storage capacity for VM virtual disks,
• one (or more) vDC Edge Gateway (VE), providing connections to external networks (internet or BVPN), as well as internal networks to the vDC.

Computing power (CPU + RAM) and storage are available according to several service classes.

Please note!
A vDC corresponds to a performance class and a resource allocation mode (PAYG or Allocation Pool). It is not possible to change the resource allocation mode of a vDC after its creation. If the Customer wishes to change the resource allocation mode of their vDC, then they must order a new vDC and migrate their vApp/VM

.

Characteristics of vDCs according to performance classes

Performance classes		Eco	Standard	High Performance	VOIP
VM Limits (vCPU / RAM / Storage)		4 vCPU / 16G / 4 TB	8 vCPU / 64G / 4 TB	32 vCPU / 256G / 6 TB	32 vCPU / 256G / 6 TB
Usage		Prod with low CPU requirements, dev, test, labs	Prod, test, dev	Prod, Big Data, real time	IPBX, real time
Allocation methods		PAYG and Allocation Pool	PAYG and Allocation Pool	Allocation Pool	Reservation Pool
One Room		▲	▲	▲	▲
Dual Room		▲	▲	▲	▲
HA Dual Room		△	▲	▲	△
Billing methods		PAYG, Mixed, Reserved and DRaaS	PAYG, Mixed, Reserved and DRaaS	Mixed and Reserved	Reserved
vCPU frequency	PAYG or DRaaS	same physical CPU	same physical CPU	N/A	N/A
	Mixed	1.7GHz	1.7GHz	same physical CPU	N/A
	Reserved	1.2 GHz min	1.2 GHz min	same physical CPU	2.6GHz

Legend

▲ Available in self-service

△ Not available

Notes:

• The mention “Same physical CPU” refers to the physical frequency of the servers deployed on the infrastructure, the frequency of which varies between 2.3 and 2.4 GHz depending on the generation of the hardware.
• In the VOIP class of service, the setting implemented disables vMotion (the automatic movement of a virtual machine from one physical server to another) and the 'VMware HA (the automatic restart of a VM hostede on a broken physical server on another physical server), this in order to be compatible with the majority's operating mode IP telephony solutions.

The different storage classes available for a performance class are presented on the Storage page.

Warning!
The virtual disk of a VM must not exceed 2 TB. Beyond this limit, the VM will continue to operate normally, but the effectiveness of the high availability and load sharing mechanisms will be affected, or even seriously disrupted. The backup will also work normally. However, restores will not work. This is why “oversized” VMs will only benefit from “Best Effort” type support.

Availability classes

On the Val de Reuil Datacenter campus, the Cloud Avenue infrastructure is deployed in two rooms, each being completely independent of the other (energy, cooling, networks), which makes it possible to offer for a vDC several availability classes:

1. OneRoom
2. Dual Room
3. HA Dual Room, also called HADR.

The full description of the availability classes is here: Availability Classes

Resource management of a vDC

The resource allocation of a vDC is chosen by the Customer. This allocation can be configured when ordering the vDC, then modified via a change request, possibly several times depending on the Customer's needs.

The resource allocation of a vDC constitutes a “physical” limit that the VMs cannot exceed in order to execute.

A VM will be able to start if the following two conditions are met:

• ∑ vCPUs of VMs already started + number of vCPUs of the VM to start ≤ total allocation in number of vCPUs of the vDC
• ∑ RAM of already started VMs + amount of RAM of the VM to start ≤ total RAM allocation of the vDC

Computing power allocation modes

Allocation mode “PAYG”

In this allocation mode, the resources are expressed in number of vCPUs (= Limit in GHz / vCPU frequency) and in GB of RAM. In a vDC configured in “PAYG” mode, the resource allocation of a VM is done at the VM level. When the VM boots, its vCPU and RAM allocation is subtracted from the total amount allocated to the vDC. A VM can never consume more than its allocation. This is a limit.

The billing method adopted is then pay-as-you-go (PAYG).

Allocation mode “Allocation Pool”

In this allocation mode, resources are expressed in GHz and GB of RAM. These resources are a maximum usage limit with a guaranteed minimum reservation. Resource allocation for all VMs is done globally when creating the VDC. Unlike PAYG, there is no limit per VM and its consumption can be adjusted according to the needs and the total use of the VMs in the VDC (without exceeding the total limit).

For resource allocation (see § 6.1.3 above), the frequency of the vCPU is defined by the Customer in reserved billing mode, when ordering the vDC, with a minimum of 1,2 GHz.

The physical processors used on the hosting platform have a frequency varying depending on the generation of physical servers, generally ranging from 2.3 to 2.6 GHz. The “Allocation Pool” mode allows the vCPU of a VM initially configured to consume up to the maximum value provided by a physical process (example: 2.3 GHz). This “burst” effect will activate under certain conditions:

• A VM subject to a high CPU load occasionally requires additional power
• There are still GHz available (not consumed) in the vDC.

This allocation mode is recommended for vDCs whose VMs are permanently on.

“Reservation Pool” allocation mode

In this allocation mode, resources are expressed in GHz and GB of RAM. But unlike the “Allocation Pool” mode, this is a firm reservation and therefore both a guaranteed minimum and a guaranteed maximum reservation. The allocation of reserved resources (therefore guaranteed minimum) of a VM is done this time individually VM by VM by the administrator of the organization throughout the life of the VDC. It is fine and total control by the administrator of the organization of his resource.

The resources allocated to each VM are 100% guaranteed for the VMs, which requires appropriate sizing when defining the VDC so that all VMs intended to operate can start.

This principle of resource allocation is used for VOIP type vDCs, which allows telephony or videoconferencing applications to operate with the maximum possible isolation from their environment.

Notes

• One might think that the “Reservation pool” mode is equivalent to the “Allocation Pool” mode where we would have reserved 100% of the limit. This is not the case because only the “Reservation Pool” mode allows a reservation at the VM level.
• If, however, you wish to reserve as much as the limit without ever having the need to reserve at the VM level, you can use an “allocation pool” mode (this is not recommended for VOIP type applications).

Computing power billing methods

Four billing methods are available.

Billing methods	PAYG (For use)	Mixed	Reserved	DRaaS
Resource allocation	PAYG	Allocation Pool	Allocation Pool Reservation Pool	PAYG
Billing	resources allocated to started VMs	% of vDC resources according to service class + resources allocated to started VMs	100% of vDC resources	resources allocated to started VMs

In Mixed mode, part of the vDC resources is billed monthly, based on the average value observed of the resources allocated during the month. Depending on the class of service, this invoiced reservation is detailed in the Price Sheet.

"PAYG" and "DRaaS" billing methods

PAYG & DRaaS	Computing power	RAM
Invoiced resources (OU)	vCPU	Go
Quantities invoiced	Number of vCPUs allocated to each started VM X number of minutes / day	Amount of RAM allocated to each started VM X number of minutes / day

The usage time is counted down to the minute.

A vDC in DRaaS mode is used in the case of setting up VM replication between the Client's private infrastructure (On Premise) and the 'Flexible Computing Advanced platform.

"Reserved" billing method

In this model, all the GHz and RAM resources of the vDC are billed as a flat rate. This principle allows the Customer to benefit from more attractive prices.

Reserved	Computing power	RAM
Invoiced resources (OU)	GHz	Go
Quantities invoiced	Quantity of GHz allocated to the vDC X number of days / month	Quantity of GB allocated to the vDC X number of days / month

Example

A vDC of 34 GHz and 20 GB of RAM is subscribed to “Reserved”. The monthly billing for this vDC is calculated as follows:

• 34 GHz x unit price x 30 days x 24h
• 20 GB of RAM x unit price x 30 days x 24h

This model also allows the client to choose their level of over-allocation. For example, by choosing a 1.7 GHz vCPU, it will be possible to start 20 VMs with 1 vCPU and 1 GB of RAM. And the most CPU-intensive VMs will then be able to draw on the GHz which are not consumed by the least active VMs (Burst effect), but within the limit:

• GHz available globally in the vDC (34 GHz)
• physical CPU frequency: 2.3 GHz.

"Mixed" billing mode

Mixed	Computing power	RAM
Invoiced resources (OU)	GHz	Go
Quantities invoiced	% of the amount of GHz allocated to the vDC	% of the amount of GB allocated to the vDC

In this model, the following are invoiced:

• The allocation of VMs in GHz and RAM on a pay-as-you-go basis (PAYG),
• Part (30%) of the vDC allocation in GHz and RAM as a lump sum payment (reserved).

The working units are GHz and GB of RAM.

This principle combines the flexibility of the PAYG mode and the advantages of reserved mode pricing.

Example

In a vDC with 26 GHz and 30 GB of RAM, the vCPU frequency being 1.7 GHz, which makes 15 vCPUs available in this vDC.

VMs are started, for an allocation of 15 vCPU, or a total theoretical consumption of 25.5 GHz. In reality, some VMs do not consume part of the GHz allocated to them, and the actual consumption is around 15 GHz. The unused 11 GHz is available in the vDC for any VM that needs more power. Thus, a VM having 2 vCPUs of 1.7 GHz = 3.4 GHz, will be able to consume up to 2 x 2.3 GHz = 4.6 GHz, i.e. a “Burst” of 35%, and always within the limit of vDC allocation.

Return to NUP Service Catalog