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I'm planning to virtualize some Linux hosts that I've got, and I'm going to be putting ESXi on the physical machines. Currently, I've got two switches set up for redundancy, and I've got bonding setup in mode 1 (active/backup).

Here's the simple logical layout: logical_switch_diagram

Essentially, any switch, NIC, or firewall can die and everything still maintains connectivity.

I would very much like to continue this when I move to ESXi, but I haven't seen any evidence that it's possible (in fact, Duncan Epping from Yellowbricks indicates that it might not be possible, if I'm understanding the question and answers correctly).

Since I am relatively new to this whole "bare-metal virtualization" thing, I figured I'd ask people who knew more than me.

Can you set up your NICs in ESXi to be highly available? And if so, how?

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up vote 6 down vote accepted

It's SO easy it's not true, you simply define your vswitches and attach two or more physical NICs to them using the GUI, each NIC is then capable of carrying the traffic from your VMs (which don't need to know that their underlying networks are protected) or the service console. There are a number of load-balancing policies to choose, from a simple failover option to ones that truly balance your traffic across as many NICs as you've assigned.

I'm sure you'll find it very easy but if you have any queries just ask ok.

EDIT - here's how it appears on one of my boxes, showing two vswitches (one for management, one for VM traffic), it really is that simple.

alt text

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Awesome, that's simple! Thanks! – Matt Simmons Jan 29 '10 at 15:36
That sounds super simple indeed. I guess that this only works for redundancy - can you do bonding where each interface is connected to a different switch. vSwitches are only on vSphere (ESX 4.0) right? Gotta upgrade our clusters! – dunxd Jan 29 '10 at 15:45
@dunxd, that method works for v3 and v4 and covers both redundant connections to the same or different switches as well as multiple-member trunks to single or multiple switches - basically pretty much any config you want :) – Chopper3 Jan 29 '10 at 15:59
I also enjoy The Great vSwitch Debate.… – Arie K Jan 29 '10 at 17:15

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