Understanding Network Virtualization in SCVMM 2012 R2

Networking in SCVMM is a communication mechanism to and from SCVMM Server, Hyper-v Hosts, Hyper-v Cluster, virtual machines, application, services, physical switches, load balancer and third party hypervisor. Functionality includes:

SCVMM Network

Logical Networking of almost “Anything” hosted in SCVMM- Logical network is a concept of complete identification, transportation and forwarding of Ethernet traffic in virtualized environment.

  • Provision and manage logical networks resources of private and public cloud
  • Management of Logical networks, subnets, VLAN, Trunk or Uplinks, PVLAN, Mac address pool, Templates, profiles, static IP address pool, DHCP address pool, IP Address Management (IPAM)
  • Integrate and manage third party hardware load balancer and Cisco virtual switch 1000v
  • Provide functionality of Virtual IP Addresses (VIPs), quality of service (QoS), monitor network traffic and virtual switch extensions
  • Creation of virtual switches and virtual network gateways

Network Virtualization – Network virtualization is a parallel concept to a server virtualization, where it allows you to abstract and run multiple virtual networks on a single physical network

  • Connects virtual machines to other virtual machines, hosts, or applications running on the same logical network.
  • Provides an independent migration of virtual machine which means when a VM moved to a different host from original host, SCVMM will automatically migrate that virtual network with the VM so that it remains connected to the rest of the infrastructure.
  • Allows multiple tenants to have their own isolated networks for security and privacy reason.
  • Allows unique IP address ranges for a tenant for management flexibility.
  • Communicate using a gateway of a site or a different site if permitted by firewall
  • Connect a VM running on a virtual network to any physical network in the same site or a different location.
  • Connect cross-network using an inbox NVGRE gateway that can be deployed as a VM to provide this cross-network interoperability.

Network Virtualization is defined in Fabric>Networking Tab of SCVMM 2012 R2 management console. Virtual Machine networking is defined in VMs and Services>VM Networks Tab of SCVMM 2012 R2 management console.

Host Config

Network virtualization terminology in SCVMM 2012 R2:


Logical networks: A logical network in VMM which contains the information of VLAN, PVLAN and subnets of a site in a Hyper-v host or a Hyper-v clusters. An IP address pool and a VM network can be associated with a logical network. A logical network can connect to another network or many network or vice-versa. Cloud function of each logical network is:

Logical network Purpose Tenant Cloud
External ·Site-to-site endpoint IP addresses

·Load balancer virtual IP addresses (VIPs)

·Network address translation (NAT) IP addresses for virtual networks

·Tenant VMs that need direct connectivity to the external network with full inbound access

Infrastructure Used for service provider infrastructure, including host management, live migration, failover clustering, and remote storage. It cannot be accessed directly by tenants. No
Load Balancer ·Uses static IP addresses

·Has outbound access to the external network via the load balancer

·Has inbound access that is restricted to only the ports that are exposed through the VIPs on the load balancer

Network Virtualization · This network is automatically used for allocating provider addresses when a VM that is connected to a virtual network is placed onto a host.

·Only the gateway VMs connect to this directly.

· Tenant VMs connect to their own VM network. Each tenant’s VM network is connected to the Network Virtualization logical network.

·A tenant VM will never connect to this directly.

·Static IP addresses are automatically assigned.

Gateway Associated with forwarding gateways, which require one logical network per gateway. For each forwarding gateway, a logical network is associated with its respective scale unit and forwarding gateway. No
Services · The Services network is used for connectivity between services in the stamp by public-facing Windows Azure Pack features, and for SQL Server and MySQL Database DBaaS deployments.

·All deployments on the Services network are behind the load balancer and accessed through a virtual IP (VIP) on the load balancer.

·This logical network is also designed to provide support for any service provider-owned service and is likely to be used by high-density web servers initially, but potentially many other services over time.


IP Address Pool: An IP address pool is a range of IP addresses assigned to a logical network in a site which provides IP address, subnets, gateway, DNS, WINS related information to virtual machines and applications.

Mac Address Pool: Mac Address Pool contains default mac address ranges of virtual network adapter of virtual machine. You can also create customised mac address pool and assign that pool to virtual machines.

Pool Name Vendor Mac Address
Default MAC address pool Hyper-V and Citrix XenServer 00:1D:D8:B7:1C:00 – 00:1D:D8:F4:1F:FF
Default VMware MAC address pool VMware ESX 00:50:56:00:00:00 – 00:50:56:3F:FF:FF

Hardware Load Balancer: Hardware load balancer is a functionality within SCVMM networking to provide third party loading balancing of application and services. A virtual IP or IP address Pool can be associated with hardware load balancer.

VIP Templates: VIP templates is a standard template used to define virtual addresses associated with hardware load balancer. VIP is allocated to application, services and virtual machines hosted in SCVMM 2012 R2. A template that specifies the load-balancing behaviour for HTTPS traffic on a specific load balancer by manufacturer and model.

Logical Switch: logical switches act as containers for the properties or capabilities that you want network adapters to have. Instead of configuring individual properties or capabilities for each network adapter, you can specify the capabilities in port profiles and logical switches, which you can then apply to the appropriate adapters. Logical switches act as an extension of physical switch with a major difference that you don’t have to drive to data center, take a patch lead and connect to computer, then configure switch ports and assign VLAN tag to that port.  Logical switch where you define uplinks or physical adapter of Hyper-v hosts, associate uplinks with logical networks and sites.

Port Profiles: Port profiles act as containers for the security and privacy that you want network adapters to have. Instead of configuring individual properties or capabilities for each network adapter, you can specify these capabilities in port profiles, which you can then apply to the appropriate adapters. Port profiles are associated with an uplinks in logical switch.

Port Classification: Port classifications provide global names for identifying different types of virtual network adapter port profiles. A port classification can be used across multiple logical switches while the settings for the port classification remain specific to each logical switch. For example, you might create one port classification named FAST to identify ports that are configured to have more bandwidth, and another port classification named SLOW to identify ports that are configured to have less bandwidth.

Network Service: Network service is container whether you can add Windows and non-Windows network gateway and IP address management and monitoring information. An IP Address Management (IPAM) server that runs on Windows Server 2012 R2 to provide resources in VMM. You can use the IPAM server in network resource tab of SCVMM to configure and monitor logical networks and their associated network sites and IP address pools. You can also use the IPAM server to monitor the usage of VM networks that you have configured or changed in VMM.

Virtual switch extension: A virtual switch extension manager in a SCVMM allows you to use a software based vendor network-management console and the VMM management server together. For example you can install Cisco 1000v extension software in a VMM server and add the functionality of Cisco switches into the VMM console.

VM Network: A VM network in a logical network is the endpoint of network virtualization which directly connect a virtual machine to allow public or private communication among VMs or other network and services. A VM network is associated with a logical network for direct access to other VMs.

VM Networks

Related Articles:

Cisco Nexus 1000V Switch for Microsoft Hyper-V

How to implement hardware load balancer in SCVMM

Understanding VLAN, Trunk, NIC Teaming, Virtual Switch Configuration in Hyper-v Server 2012 R2

How to configure SMB 3.0 Multichannel in Windows Server 2012 Step by Step

SMB Multichannel

The SMB protocol follows the client-server model; the protocol level is negotiated by the client request and server response when establishing a new SMB connection. Windows Server 2012 introduces a feature called SMB 3.0 Multichannel. Multichannel provides link aggregation and fault tolerance.

SMB 3.0 introduces multipath I/O (MPIO) where multiple TCP connections can be established with given SMB session. Benefits include increase bandwidth, enable transparent network interface failover and load balancing per session.

SMB Encryption

Open following registry key


  • If value of EncryptData DWORD is set to 0 then communication between SMB client and server is encrypted
  • If value of RejectUnencryptedAccess DWORD is set to 1 then communication between SMB client and server is rejected.

SMB Multichannel Requirement:

  • At least two computers that run on Windows Server 2012 R2, Windows Server 2012, or Windows 8 operating systems. No additional features have to be installed—SMB Multichannel is enabled by default.
  • Multiple network adapters in all hosts
  • One or more network adapters that support Receive Side Scaling (RSS)
  • One of more network adapters that are configured by using NIC Teaming
  • One or more network adapters that support remote direct memory access (RDMA)
  • Both NICs must be in different subnets
  • Enable NICs for client access
  • Dedicated subnets SMB storage
  • Dedicated Storage VLAN depending on if/how you do converged fabrics
  • VNX File OE version 7.1.65 and later or SMB 3.0 compliant storage
  • Port Channel Group configured in Cisco switch

TCP/IP session without Multichannel Session

  • No Automatic failover or Automatic failover if NICs are teamed
  • No Automatic failover if RDMA capability is not used
  • Only one NIC engaged
  • Only one CPU engaged
  • Can not use combined NIC bandwidth

TCP/IP session without Multichannel Session

  • Automatic failover or faster automatic failover if NICs are teamed
  • Automatic failover if RDMA capability is used. Multiple RDMA connection
  • All NICs engaged
  • CPU work load shared across all CPU cores
  • Combine NIC bandwidth

Which one to use, RDMA or RSS?

If you are looking fault tolerance and throughput then obvious choice is NIC teaming with RSS.

Adding a SMB Share in VNX Storage

  1. Create a network. Go to Settings -> Network -> Settings for File, Setup your network information
  2. Go to Storage -> Storage Configuration -> File Systems to create storage. Setup your storage configuration
  3. Go to CIFS Servers tab and create your Server configuration.
  4. Go back to your CIFS Share configuration and assign your CIFS Server as allowed and allow SMB protocol.
  5. Connect your CIFS Share with \\CIFSServer\CIFSShare and your new administrator password.

Adding a port channel group in Switch

Configuration of Cisco Switch with 2 network ports (If you have Cisco)

Switch#conf t
Switch(config)#Int PORT (a.e. Gi3/1)
Switch(config)#switchport mode access
Switch(config)#spanning-tree portfast
Switch(config)#channel-group <40> mode active
Switch(config)#Int port (a.e. Gi3/1)
Switch(config)#switchport mode access
Switch(config)#spanning-tree portfast
Switch(config)#channel-group <40> mode active

Configuration of HP Procurve with 2 network ports (If you have HP)

PROCURVE#conf ter
PROCURVE# trunk PORT1-PORT2 (a.e. C1/C2) Trk<ID> (a.e. Trk99) LACP
PROCURVE# untagged Trk<ID> (a.e. Trk99)
PROCURVE# show lacp
PROCURVE# show log lacp

Adding SMB 3.0 Share in Hyper-v

  1. From Server Manager, click Tools and then click Hyper-V Manager
  2. Click Hyper-v Settings, Click Virtual Hard Disk, Type UNC path of SMB 3.0. Click Virtual Machine, Type UNC path of SMB 3.0
  3. Click Ok.
  4. Open PowerShell Prompt, Enable Multichannel using the following cmdlets.
  5. Configure SMB Multichannel using Windows PowerShell

Get-SmbClientConfiguration | Select EnableMultichannel

Get-SmbServerConfiguration | Select EnableMultichannel

    6. Enable Multichannel

Set-SmbServerConfiguration -EnableMultiChannel $true

Set-SmbClientConfiguration -EnableMultiChannel $true

   7. Verify Multichannel