Configure the Fabric (27%)
Configure the network fabric
System Center 2012 Virtual Machine Manager can be used to configure the network fabric. This includes:
- Logical Networks and Network Sites - A logical network together with one or more associated network sites is a user-defined grouping of IP subnets that is used to simply network assignments. Logical networks are a simplification of networking that is user-friendly.
Network sites are one more subnets, VLANs or subnet/VLAN pairs that are associated with a Logical Network. Network sites must be bound to a Host Group when they are created.
- Virtual Networks
- IP Address Pools
- MAC Address Pools
- Load Balancers
It's a good idea to draw out your network design, prior to implementation. Here you can see I have drawn out the network design, later I will implement the design in VMM.
Create a Logical Network
In the example below, I will create a logical network for Production. I will assign 2 sites to the logical network, one called Brisbane and one called Sydney.
When assigning VLANs and Subnets to sites, the IP Subnet is only required if you will be using IP Pools. The VLAN is required if you want VMM to automatically assign VLANs to your virtual machines.
You can use the hardware tab of the Host properties to assign a network adapter to a logical network.
Create an IP Address Pool
Creating an IP Address Pool is very similar to creating a DHCP scope, you have to configure the same options, including:
- Starting and ending address
- Excluded IP Addresses (called Reservations)
- Default Gateway
- DNS Servers and DNS Suffix
The only option that is really different from a DHCP scope is the VIP address range. These are used to assign Virtual IP Addresses when using Load Balancers.
In the screenshot below, you can see I have set the currently used addresses as excluded. I have also defined a range of 20 IP addresses that can be used for load balancer VIPs as required.
As you can see below, the newly created IP Pool has been configured and is ready for use.
Configure MAC Address Pools
By default, Virtual Machine Manager has two MAC Address Pools, one for Hyper-V and one for vmware. You can create additional MAC Address Pools if required. MAC Addresses that have been allocated to virtual machines can be released back to the pool, this occurs automatically when a virtual machine is deleted.
Configure Load Balancing
I have a Citrix NetScaler Load Balancer, so I'm going to install the provider (LINK) onto my VMM Server. If you want to try a Citrix NetScaler, Citrix have a 90-day free trial available that'll work well for testing purposes.
Restart the VMM service before continuing or you will get the following error:
Fire up the VMM console and add the load balancer.
Because I will be load balancing internal resources, I have selected both checkboxes below. I do not have a separate front-end network e.g. Perimeter Network.
You can see in the screenshot below that the provider does not yet support Citrix NetScaler 10.x so I won't be able to use my NetScaler with VMM. Unfortunate, but at least you get an idea of how to add a load-balancer to VMM.
VIP Templates are a set of configuration settings that define the setup of a Virtual IP (VIP) Address. The following settings are available:
- Template Type
- Protocol - Including HTTPS pass-through/terminate settings
- Persistence - Source IP, Cookie Insert, etc
- Method - Round Robin, Least Connection, etc
- Health Monitors - Status checks for a server behind a VIP
The options available when creating a VIP are dependent on the load balancing provider, NLB has fewer options than what is available when you select the NetScaler provider (one example is the health monitoring features).