Updating ESXi 6 Hypervisor to ESXi 6 U2

1. Enter ESXi Maintenance mode
   

   
2. Download update-from-esxi6.0-6.0_update02.zip, upload to ESXi using Datastore Browser.  (Search for latest update here with your VMWare account.  https://my.vmware.com/group/vmware/patch#search)
   

   
   

   
3. use PuTTY to SSH in and type this install command: (determine the volume name with df command) 

esxcli software vib install -d /vmfs/volumes/Esxi1-Datastore/update-from-esxi6.0-6.0_update02.zip

Substituting the "Esxi1-Datastore" part with the full path to your .zip file. Tab/type-ahead is your friend!

4. After the patch install , ESXi host will reboot automatically. If not manually issue the reboot or  poweroff command.

5. verify the new build that's seen as the system reboots. After boot, an alternative is to use the vSphere Web Client, select the host, select Summary, then select the Configuration pane.