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So many network cards

1. Do Hyper-V virtual machines require their own virtual NIC or can they pass through and use the host's NIC?  Advantages and disadvantages?
2. How do control which NIC responds to a DNS query when there are multiple NICs on a server?
3. When you have physical NICs, virtual NICs, and NICs for iSCSI traffic all on one host, how do you recommend naming the NICs?
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ArneLovius
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There was a good tutorial explaining Hyper-V networking written by Brien Posey a while back that might be of some help
http://www.virtualizationadmin.com/articles-tutorials/microsoft-hyper-v-articles/networking/virtual-networking-hyper-v-part1.html
Or a mimi- article on the Microsoft MSDN site:
http://blogs.msdn.com/b/virtual_pc_guy/archive/2008/01/08/understanding-networking-with-hyper-v.aspx
If you have a San its common practice to have at least two: One for the San and one for everything else. If possible id try to get a quad port and link aggregate a few for all the vms out the LAN so they can share instead of dedicating one per vm.
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ArneLovius, can you rephrase or elaborate a bit on your answer to #2?

Thanks!
A NIC does not respond to a DNS request, a DNS server responds to a DNS lookup request.

Perhaps you meant something about active DNS registration ?

A NIC in a hyper-v server that is dedicated to guest use, is not accessible to the host .

Perhaps you could rephrase or elaborate your question :-)
Hello ArneLovius,
You are right I need to rephrase this question...

If I ping a host that has a shit ton of NICs on it, how does DNS now which of the IPs to reply with?  

Or how about if I ask it this way...

When there are ten NICs for one host name, can I control which of the ten IPs is the default for replies to DNS requests?

Josh
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Ok so if I want to connect to a host via a particular network card on that host, it sounds like the best thing is to use the IP address for that network card.

Because if I just use the host name, you can't control which of the multiple valid IP addresses DNS might give you.  I don't see anything in the DNS 'A' records that makes one 'A' record take precedence over another 'A' record.

I do see in the network adapter properties a check box that determines whether an adapter will register with DNS or not.  So for some adapters that don't need that, in some cases, perhaps we can uncheck that box (I don't know for sure yet).  That would reduce the amount of entries in DNS for the same host.
a NIC that is dedicated for guests is not accessible to the host

iSCSI NICs are not accessible to the host

how many NICs do you have left ?
Trying to help someone else with this question...  this is what he answered:

"1 team nic which uses 2 physical nics LACP"
a teamed NIC has one IP address...
Maybe some of the iSCSI or virtual NICs are showing in DNS that should not be, I will look into this further, thanks for all the info