updating NIC drivers on VMware ESX host

Print out lost of info on the host, you can grep for the NIC you are looking for
esxcfg-info -n | less

List all the NIC info
esxcfg-nics -l

Show the driver and firmware version for vmnic0
ethtool -i vmnic0

Show the VMware version on the host
vmware -l

Check vmware compatibility guide
http://www.vmware.com/resources/compatibility/detail.php?deviceCategory=io&productid=21553&deviceCategory=io&details=1&partner=146&releases=260&deviceTypes=6&vioSolutions=Standard%20-%20IO%20Devices&page=1&display_interval=10&sortColumn=Partner&sortOrder=Asc

Check the compat guide for the latest driver for your NIC and your version of VMware update X.

Download the driver file and extract it. You want the .VIB file

You will need to enable ssh and esxcli on your host
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2004746

SCP the vib file to the host

Migrate all VMs off the host

Put the host into maintenance mode

Turn on logging in your putty session in case anything goes wrong you have some output for support.

Update the driver with the new VIB file
esxcli software vib update -v {VIBFILE}

Note: Depending on the certificate used to sign the VIB, you may need to change the host acceptance level.  To do this, use the following command:
esxcli software acceptance set --level=<level>

Reboot the host and test connectivity

Don't forget to turn off esxcli and ssh when you are done