Dedicated NIC for each VM VS a single NIC

[pilot8]

Hello,

Am wondering what would be the advantage or disadvantage of having dedicated NICs per VM. currently I have 11 VMs on a Vsphere 4 update 1 and all this VMs which are windows 2008R2s are going through VMNIC0 to a GBit switch port. So If I loose this port, I would loose connections to all 11 VMs and with 11VMs, and 1 GBit port, the bandwidth would be limited. I would like to dedicated 4 ports on the physcal switches to 4 very important VMs. I have 8 NICs total in the ESX host. This way, the 4 VMs would not share the same port VMNIC0, and will have it's dedicated bandwidth 1GB each.

Is this possible, recommended practice ? will it provide performance and bandwidth?

Your comments are appreciated!

Jay

[vmroyale]

Hello.

Am wondering what would be the advantage or disadvantage of having dedicated NICs per VM.

Possibly the biggest disadvantage would be scalability of this design. Do you have baselines or traffic data for these virtual machines? I would bet that the chances are good that they do not require a dedicated Gig nic each.

The easiest way to get some redundancy would be to add another nic to your vSwitch. But there are probably even better ways to set this up, like separate vSwitches for each function. How many vSwitches do you have currently and how are they configured? It sounds like the default setup was used vmnic0 has the service console and a virtual machine network. Also, are you using NAS or iSCSI for your storage? Vmotion or FT being used at all? DMZ traffic? If you can tell us a bit more about the setup, then we can provide you with more options.

Good Luck!

[kish09]

Hi

i would recommend you to make a ether channel of 4-4 pair in active -passive from diff physical switch(like one pair is frm SW1 and other is from SW2).in this way you can get 4 gbps speed.the pair active on vSwitch0 will be used as passive on vSwitch2.like this way.this way you can get better bandwidth of 4 gbps with redundancy.

thnx.

[pilot8]

Hi,

see answers to your questions:

The easiest way to get some redundancy would be to add another nic to

your vSwitch. But there are probably even better ways to set this up,

like separate vSwitches for each function. How many vSwitches do you

have currently and how are they configured?

1. 1 physcal switch

It sounds like the default

setup was used vmnic0 has the service console and a virtual machine

network.

1. I have separated vmnic0 to only support console.

#virutal machines are in VMNIC2 and on it's own Vswitch.

Also, are you using NAS or iSCSI for your storage?

We are using ISCSI with SAN in the backend. 2 DUAL HBAS

Vmotion or

FT being used at all?

None...

DMZ traffic?

None.

If you can tell us a bit more

about the setup, then we can provide you with more options.

thanks!

Jay

[pilot8]

Hi,

Thank you for your response. I only have 1 physcal GBit switch and a ISCSI SAN in the backend.

Jay

[AndreTheGiant · Accepted solution]

If you need the best of the performance you can use VMDirectPath and assign a dedicated physical network card to a VM.

See:

But in this way you loose flexibility and VMotion.

If you availability use more than one NIC for your vSwitches.

If you need also performance use more NICs.

Andre