network interface speed

[mful]

I have 2 1gb interfaces (eth0/eth1) on the host and bonded as bond0. The bond is configured for 802.3ad (link aggregation where traffic is distributed on the basic of source/destination addresses). The upstream switch ports are members of a trunk and are configured LACP.

Questions:
1. If only one, 1gb interface is used on the guest (bridged to bond0) and given that it is not a physical device, can both links on the host be driven at full speed when talking to multiple clients?

2a. Or do you have to configure the guest with 2 interfaces, each bridged to a slave, and bond them in the guest? I am not sure if this works. I have tried a configuration where one i/f was bridged to eth0 (a slave). I could ping the host but not other devices, but there may have been a config problem elsewhere.

2b. Can you have multiple guests, each with a bond0?

Although I have asked a couple of questions addressing my specific problem, what I really want is to gain a better understanding of the subject of bonding. Links to other material would be good. The linux bonding howto is good but I still have lots of questions.

[Sasquatch]

When you use bridged networking, you select the interface that you are using on the Host. If this means that you have bonded two or more physical interfaces to one virtual one, you select the virtual one. This because the physical interfaces are no longer managed by the system, they are managed by the bonding software/modules. This then means that the bonding options you set on the Host should also be valid for the Guest that use it.

The effective speed you get is not equal to the link speed you see inside the Guest. In the past, it's proven that a 10/100 Mbit virtual interface was able to achieve higher speeds than the theoretical maximum when the physical network exceeds that. E.g. a VM with a NIC set to 100 Mbit got 20 MB/s throughput when used on a gigabit network. Same can happen when you use a 10 Mbit NIC .