Your network contains five servers that run Windows Server 2012 R2.
You install the Hyper-V server role on the servers. You create an external virtual network
switch on each server.
You plan to deploy five virtual machines to each Hyper-V server. Each virtual machine will
have a virtual network adapter that is connected to the external virtual network switch and
that has a VLAN identifier of 1.
Each virtual machine will run Windows Server 2012 R2. All of the virtual machines will run
the identical web application.
You plan to install the Network Load Balancing (NLB) feature on each virtual machine and
join each virtual machine to an NLB cluster. The cluster will be configured to use unicast
only.
You need to ensure that the NLB feature can distribute connections across all of the virtual
machines.
Solution: From the properties of each virtual machine, you enable MAC address spoofing for
the existing virtual network adapter.
Does this meet the goal?
A.
Yes
B.
No
In order to do what’s required.
You’d need to enable a multicast mode because each virtual machine will have only 1 virtual network adapter. But since the requirement is to use Unicast only.
According to the Exam Ref Guide 70-414, Page72
“Unicast is appropriate when there’s more than one network adapter in the host.”
Thus, the solution is to add another virtual adapter to each VM and connect it to another virtual switch for internal cluster communication. Mac spoofing is what will happens then, afterwords.
So the answer is NO. Because, can’t do unicast with 1 NIC.
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given answer is A ..
https://technet.microsoft.com/en-us/library/cc782694%28v=ws.10%29.aspx
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Agree with Peter .. Unicast requires 2 NICS
Answer is B. NO Does not meet the goal
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Unicast requires 2 NICs to communicate with the host. This question just requires the VM’s to talk to each other. I think it is YES.
http://www.hyper-v.nu/archives/mvaneijk/2013/06/system-center-2012-sp1-service-provider-foundation-high-availability/#more-4676
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@ John – you might just be right about that and these links might add weight/explain your argument but I will deep dive the scenario some more to see what else I can come up with as Im still not 100% sure
http://blogs.technet.com/b/networking/archive/2010/02/12/cannot-access-the-virtual-or-dedicated-ip-address-of-an-nlb-node-guest-running-in-unicast-mode-on-windows-server-2008-r2-hyper-v.aspx
https://blogs.technet.microsoft.com/jhoward/2009/05/21/new-in-hyper-v-windows-server-2008-r2-part-2-mac-spoofing/
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has to be legacy NIC for “enable MAC address spoofing”, so the answer should be NO
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This WILL meet the goal, correct answer is A) Yes.
1. JamesL was wrong, Unicast does NOT require two NICs. However, if you do have two NICs then Microsoft RECOMMENDS using Unicast mode: https://technet.microsoft.com/en-us/library/cc756878(WS.10).aspx
2. “When unicast NLB nodes respond to an ARP request with an ARP response, they don’t use their actual MAC address in the Ethernet Source Address field. This is because in unicast NLB the Virtual MAC address 02-BF-XX-XX-XX-XX will override the actual MAC address of the NIC so the nodes will use the spoofed MAC address (02-HostID-XX-XX-XX-X) for all outbound packets to keep the network switch from learning the virtual MAC address of the NLB nodes.
The virtual switch in Windows Server 2008 R2 has MAC Spoofing disabled by default on all ports which will drop the packet when it finds the spoofed MAC address in the Ethernet Source Address Field which is different than actual MAC address”
“To resolve this issue, enable MAC address spoofing on the network adapter of the virtual machine (guest machine)”
Source: https://blogs.technet.microsoft.com/networking/2010/02/12/cannot-access-the-virtual-or-dedicated-ip-address-of-an-nlb-node-guest-running-in-unicast-mode-on-windows-server-2008-r2-hyper-v/
3. “I have chosen for NLB in Unicast Mode with a single NIC per server. In Windows Server 2008 Microsoft enabled the UnicastInterhostCommSupport by default. This allows the individual hosts to communicate with each other despite the server MAC address being overruled by the cluster MAC address.
Before configuring NLB in the virtual machines there is one essential settings that must be changed on the virtual machines. For an average virtual machine this is desirable, but NLB needs to overrule the individual server MAC address with the cluster MAC address.”
Source: http://hyper-v.nu/archives/mvaneijk/2013/06/system-center-2012-sp1-service-provider-foundation-high-availability/#more-4676
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