Questions about cabling ESX hosts to physical network switches

We have 3 ESX 3.5 update 1 hosts in a VMware cluster. Each ESX host has 6 network cables attached: 1 cable is dedicated to VMotion, 1 cable is dedicated to DMZ traffic, and the four remaining cables are connected to the internal VMware switch which handles local LAN traffic. Each ESX host has five of it's cables connected to a unique Dell network switch. The DMZ cables are attached to one switch that has a VLAN for the DMZ traffic.All networking has worked fine so far. We don't have any trunking, etc. setup on our physical network switches.

I am curious if there would be any benefit in spreading the data cables across multiple network switches, or if it's better for each ESX host to be dedicated to one switch.

Configuration:

• ESX host 1 has four data cables and one vmotion cable attached to switch 1.

• ESX host 2 has four data cables and one vmotion cable attached to switch 2.

• ESX host 3 has four data cables and one vmotion cable attached to switch 3.

• ESX hosts 1, 2 and 3 each have one DMZ cable that use 4 ports on switch 1.

• The DMZ cables are associated with a VLAN. The additional DMZ cable in the VLAN comes from our firewall into switch1.

1. On the one hand, isolating network cables to one switch means that if that switch ever goes down, only one ESX host would be affected. The bad news is that all of the VMs on the ESX host with the bad physical network switch would be shutdown and restarted on another ESX host if the switch was not functioning.

2. Alternatively, if ESX host 1 had two data cables on switch 1, and two data cables on switch 2, then the load would be over more than one switch. But I wonder if the network traffic would be less efficient because one ESX host is sending/receiving data over two physical switches. Are there any other reasons this approach would be good/bad?

3. Also, is there any benefit to putting all the Vmotion cables on one switch with it's own VLAN? Is there any benefit to that approach vs having three VMotion cables each connected to a unique physical network switch ?

4. What benefit could be gained by trunking our data cables vs not trunking them?

Thanks, Andoven