Hyper-v....multiple vnics?

Soldato
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Hi all,
i have 4 hyper-v on 2008 R2 Enterprise.
I'll be using all 4 physical nics (one for each vm), but do i need to create a separate virtual network for each one.
I'm assuming not (even though i have done). Is there any benefit to doing so, if only one vm will be hanging off each physical adapter?
 
If you want to use 4 NICs, then you have to create 4 virtual external networks...... unless you have compatible drivers that allow you to team the 4 NICs into one, then you can create a single virtual external network that all 4 VMs use.
 
I have done it in a very similar way without issue...

I have 4 NICs and two teams. One team is used by the host, and the other team I have assigned to a single Virtual Network used by 2 VMs.

I dont think however there is anything to stop you assigning more than 1 virtual network to a single NIC/team..but I would be keen to hear if there is a better way of doing it.

My thoughts that creating a single virtual network and assigning to a single NIC per VM is not such a good idea because you lose fault tolerance if that partiuclar port was to give up the ghost.
 
Thanks.
I think i've gone and ballsed something up.
Remoting into the host via the unteamed nic keeps freezing on me.
So i've added it back into the team, but now i can't assign it a manual IP (?) and thus cannot remote back into it, even though i'm using its netbios name not IP to connect to.
 
I think the reason for that is when you assign a team to a Virtual Network in Hyper-V, the TCP/IP config is then done in guest OS's - not the host, so is unavailable on the host. (I may be totally wrong, it's just my take on it..so do correct me if I'm wrong)

Looking at the team that I use for Hyper-V (from the host) is very much the same scenario..IE I cannot set any IPv4/v6 there.

The team itself only shows as a single NIC to the guest.

I assume therefore you will have to remove it from the team used by the virtual network to fix it, or alternatively, tick the option to "allow the management system to share this network adapter" in Hyper-V network settings
 
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If you've added the last remaining NIC to the team and not set the host OS access then it's either ILO or visit the machine time to sort it out.

Ideally you should always leave a single NIC for management, and set the NICs for VM's as not allowed for host access - just keeps it easier. You can't attach a physical NIC or Team to more than 1 virtual network. If you can team them and have a need to do so, then team the 3 NICs and set up 1 virtual network, other wise setup the 3 NICs unteamed on 3 seperate virtual networks. Each VM can have multiple virtual NICs on different networks, or even on the same network if you like.
 
You can, if the NIC/Team supports VLANs

No you can't. You can only bind 1 physical NIC or Team to a virtual network switch. Once any adaptor / team is bound to the Virtual Network Switch Protocol, it can not be added to a second virtual network switch.
 
No you can't. You can only bind 1 physical NIC or Team to a virtual network switch. Once any adaptor / team is bound to the Virtual Network Switch Protocol, it can not be added to a second virtual network switch.

Actually for the broadcom adaptor i have tested it on, when you create 2 VLANs on a single team. the OS sees it as 2 network adaptors. Each one can be bound to a different vSwitch.

EDIT: Actually what am i talking about "tested" Our live HV cluster has it set up like that.
 
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Could you share how you have managed this as you have managed to do something Hyper-V was never designed to do (for whatever reason even tho other hypervisors do it.....like USB passthru!! ggrrrr) and there are plenty of people who would love to be able to do this.
 
Could you share how you have managed this as you have managed to do something Hyper-V was never designed to do (for whatever reason even tho other hypervisors do it.....like USB passthru!! ggrrrr) and there are plenty of people who would love to be able to do this.

Maybe we are talking about different things, It's nothing to do with Hyper-V. After all, teaming isn't supported by Microsoft, it's fully handled by the NIC manufacturer.

Ok using the Broadcom BACS you create a Team using however many physical NICs. Then within the team options create several VLANs. This creates a BASP virtual adaptor for each VLAN. Each of these adaptors can be connected to a different vSwitch.

I'm pretty sure it can also be done with Intel Proset. But i've not tried it yet, will be playing with it a bit in the coming days though.
 
Maybe we are talking about different things, It's nothing to do with Hyper-V. After all, teaming isn't supported by Microsoft, it's fully handled by the NIC manufacturer.

Ok using the Broadcom BACS you create a Team using however many physical NICs. Then within the team options create several VLANs. This creates a BASP virtual adaptor for each VLAN. Each of these adaptors can be connected to a different vSwitch.

I'm pretty sure it can also be done with Intel Proset. But i've not tried it yet, will be playing with it a bit in the coming days though.

Indeed we have a cluster with 250 odd host vans coming into each server on a 2x 10GigE team, 2x 1GigE for management network, 1GigE for cluster and 2x8GigFC for the storage.

Works nicely eventually. For reasons Microsoft/Hitachi can't explain iSCSI did not work so nicely
 
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