Currently, this looks like:
~ # esxcfg-nics -l
Name PCI Driver Link Speed Duplex MAC Address MTU Description
vmnic0 0000:02:00.00 tg3 Up 1000Mbps Full 40:6c:8f:20:45:15 1500 Broadcom Corporation NetXtreme BCM57765 Gigabit Ethernet
Of course, the server is currently working and whatever is causing this dropout hasn't occurred yet. When the dropout happens again, I'll try running this command again to see if the output changes.