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Archive for April, 2012

Windows 8 : Why should my hardware have SR-IOV capabality ?

April 4, 2012 1 comment

Single Root I/O Virtualization (SR-IOV)

SR-IOV capability will significantly reduce the overhead on network IO operations.

It allows for a virtual machine to have near native IO against the physical NIC, allowing applications that require very low latency to work inside of virtual machines.

What does it require?

  • It must bypass teaming
  • Interrupt and DMA remapping
  • Access Control Services (ACS) on PCIe root ports
  • Alternative Routing ID Interpretation (ARI)
  • Hardware virtualization, EPT or NPT

Where to create:

– In the Hyper-V Manager, click on Virtual Switch Manager on the right panel

– Click Add New Virtual Switch

– Type the name of the virtual switch

– Tick box for Enable Single Root I/O virtualization (SR-IOV)

IMPORTANT :

More about SR-IOV here : SR-IOV feature (Single Root – I/O Virtualization)

Microsoft SR-IOV Support on Dell PowerEdge Servers (source : http://en.community.dell.com/techcenter/os-applications/w/wiki/3459.dell-supported-platforms-for-windows-server-8-sr-iov-feature.aspx):

Dell PowerEdge 12th Generation servers support the SR-IOV servers but previous generations have exceptions.

Below is a list of Dell 11th Generation platforms that support the SR-IOV feature:

  • R910

The following platforms are also supported and must be an 11G Generation II server:

  • T410, R410, R510, R610, T610, R710, T710.

How to identify an 11G Generation II system:

  1. These servers will be physically marked with symbol “II” on the Express service tag.  The Express service tag is located in front panel of the system.
  2. These systems support Intel 56XX (Westmere) processors
  3. The System Revision Field in the iDRAC GUI will have “II”

Supported SR-IOV network cards:

  • Intel X520 10GB Ethernet adapters.

Because Windows Server 8 Beta is a pre-release product still in active development, Dell does not provide any support for this pre-release software and it is not recommended for use in a production environment.

Windows Server 2012/R2 and NIC teaming modes and how to

April 2, 2012 8 comments

NIC teaming, the new feature of Windows 2012/R2, allows multiple network adapters on a computer to be placed into a team for the following purposes:

  • Bandwidth aggregation

– Traffic failover to prevent connectivity loss in the event of a network component failure

Modes:

  • Generic or static teaming (IEEE 802.3ad draft v1): This mode requires configuration on the switch and the computer to identify which links form the team. Because this is a statically configured solution, no additional protocol assists the switch and the computer to identify incorrectly plugged cables or other errors that could cause the team to fail. This mode is typically supported by server-class switches.
  • Dynamic teaming (IEEE 802.1ax, LACP): IEEE 802.1ax uses the Link Aggregation Control Protocol (LACP) to dynamically identify links between the computer and a specific switch. This enables the automatic creation of a team and, in theory, the expansion and reduction of a team simply by the transmission or receipt of LACP from the peer network adapter. Typical server-class switches support IEEE 802.1ax, but most switches require manual administration to enable LACP on the port.
  • Switch independent: do not require that the team members connect to different switches, they merely make it possible.

Characteristics:

  • It is manageable through both PowerShell and the GUI
  • Supported on various NIC types/vendors
  • You can team up to 32 NICs
  • Unlimited virtual interfaces
  • Multiple teaming modes
  • NIC teams can only be formed between homogenous NICs. So two 1GB NICs can be teamed, or two 10GB NICs can be teamed, but you cannot team a 1GB and 10GB NIC.
  • If the individual NIC  support Receive Side Scaling (RSS), the NIC team also supports RSS. Hence it is a good idea to team NICs  that support RSS. The resulting NIC team is also highly capable and does not lose any functionality.
  • If the individual NIC  supports RDMA, the resulting NIC team does NOT support RDMA. Given how Windows 8 SMB 2.2 natively supports RDMA without modifying applications, it is a bad idea to team NICs with RDMA capabilities, and where the interconnect (routers, etc) also supports RDMA

How to:

Using Powershell:

  • Static

New-NetLbfoTeam -Name “Team-Static” -TeamMembers NIC1,NIC2 -TeamingMode Static

  • Dynamic

New-NetLbfoTeam -Name “Team-Static” -TeamMembers NIC1,NIC2 -TeamingMode Lacp

  • Switch Independent

New-NetLbfoTeam -Name “Team-Independent” -TeamMembers NIC1,NIC2 –TeamingMode SwitchIndependent

More Power Shell Commands:

  • To get the Teaming proprieties and settings in PowerShell:

Get-NetLbfoTeam

  • To get all of the PowerShell commands available for NetLBFO

Get-Command -Module NetLbfo

Using GUI:

  1. Open Server Manager.
  2. In the console tree, click Local Server.
  3. In the details pane, in the Properties section, click NIC Teaming Administration under Remote Desktop.
  4. In the NIC Teaming Window, select the NIC’s to team on the bottom right on the screen
  5. Right click and select add to new team
  6. In the new team window, provide the name of the nic team(e.g. team-static)
  7. Expand the additional properties and select the team mode
  8. click OK to finalise and create the nic team.

Now you are ready to create the Hyper-v Network Switch by using the NIC team.