load balancing (nics ports)

[beckhamk]

This question is in regards to load balancing when you have a port group with two physical nics teamed for load balancing and failover.

I understand that vmware doesnt do inbound load balancing, thats fine. But I am a little confused on these two options:

1) Route based on the originating port ID - Choose an uplink based on the virtual port where the traffic entered the virtual switch.

Using nic0/nic1 - Does this mean that if inbound traffic from the outside came into nic1 all traffic going in/out stays on nic1 for the vm in question?

2) Route based on source MAC hash - Choose an uplink based on a hash of the source Ethernet.

a) Source ethernet - is this the source ip mac (external) or the source vm's nic mac (internal).

b) I assume this hash is a 0 or 1 for nic 0 or nic 1. So if this is based on vm mac then some vm's will always be placed on nic0 and other vm's will be on nic1 correct?

[RenaudL]

1) Route based on the originating port ID - Choose an uplink based on the virtual port where the traffic entered the virtual switch.

Using nic0/nic1 - Does this mean that if inbound traffic from the outside came into nic1 all traffic going in/out stays on nic1 for the vm in question?

You're taking it the wrong way: it means the traffic coming from a VM to the physical network will always be routed to the same physical nic. A consequence is that the inbound traffic for the VM will always come from the same physical nic because the physical switches route their packets looking at where the MAC address initially came from.

2) Route based on source MAC hash - Choose an uplink based on a hash of the source Ethernet.

a) Source ethernet - is this the source ip mac (external) or the source vm's nic mac (internal).

Did you mean "destination MAC"? No, the load balancing is based on the source MAC, which means that a VM will also use a single physical nic (if it only has 1 MAC address, I don't see any reason why it would have multiple ones).

b) I assume this hash is a 0 or 1 for nic 0 or nic 1. So if this is based on vm mac then some vm's will always be placed on nic0 and other vm's will be on nic1 correct?

Correct.

[beckhamk]

>You're taking it the wrong way: it means the traffic coming from a VM to the physical network will always be routed to the same physical nic. A consequence is that the >inbound traffic for the VM will always come from the same physical nic because the physical switches route their packets looking at where the MAC address initially came >from.

So when the is used, ESX will balance the each VM's nic onto either nic0 or nic1 correct?

>mac hash

So the when the term is used we are talking about the vm's mac correct?

[RenaudL · Accepted solution]

So when the is used, ESX will balance the each VM's nic onto either nic0 or nic1 correct?

Correct.

So the when the term is used we are talking about the vm's mac correct?

Well, whatever MAC is put in the "source" field of the ethernet header, which will likely be the MAC address the vnic is using.