HP Matrix 7.2 KVM Private Cloud Getting Started Guide

Table 9 Resource considerations when expanding a KVM Private Cloud (continued)
Configuration options and requirementsCloud component
Three separate networks (IP subnets) are required to provide connectivity among the KVM
Private Cloud elements.
Network
NOTE: Make sure there are sufficient IP addresses to allocate to the VM instances that
you plan to deploy. If you do not allocate enough IP addresses when you configure cloud
networking, you cannot add them later without resetting your environment.
• Host management subnet: a private (RFC 1918), non-routable network that supports
communication between the KVM Admin Console residing on the controller host and
the compute nodes.
• Cloud connectivity subnet: a public-facing network that allows end users to access the
VM instances provisioned in the KVM Private Cloud. This network should be routable
on the organization’s intranet. Plan for at least 21 subnets to ensure that there are enough
IP addresses for the VMs.
To provision the KVM Private Cloud infrastructure components through Matrix OE and
integrate the KVM Admin Console appliance with Matrix OE, some additional network
connectivity is required:
• Matrix OE access: this allows Matrix infrastructure orchestration to communicate with
the KVM Admin Console.
• Matrix OE deployment: this is used by Matrix OE to deploy operating systems on physical
KVM Private Cloud server blades.
Recommended server pool and enclosures by cloud size:Server pool resources
• Small: at least one c7000 enclosure with two VC FlexFabric modules for both network
and SAN connectivity.
• Medium/large: two or more c7000 enclosures, stacked (recommended) or unstacked,
each with two VC FlexFabric modules connected to the LAN fabric and the SAN fabric
in an active/active (recommended) or active/standby network configuration. The KVM
Private Cloud management cluster and the compute nodes can then be split across the
enclosures.
Using the KVM Admin Console, you can create an OS image from an instance snapshot
or you can import an image.
Images
A DNS server authoritative for the DNS domain name and a DHCP server should already
be configured in the Matrix Operating Environment.
DNS and DHCP
Calculating the number of VMs that can be provisioned to a host
The maximum number of virtual machines that can be provisioned to a host is based on the
following:
• the amount of installed RAM memory, available disk capacity, and number of CPU cores on
the host
• the size of the instance type of the virtual machines to be provisioned
• resource oversubscription, which is individually applied to the memory, disk, and CPU
calculation
The following resource oversubscription rates are provided so you can properly dimension the
capacity of your hosts based on virtual machine size requirements. See the HP Developer Resource
Center for CloudSystem Toolkits/Samples tab for a Microsoft Excel spreadsheet that can help you
calculate your host size requirements.
NOTE: In this release, these rates cannot be changed.
20 Plan an expansion of the cloud