The esxcli command set is based in a "namespace" model. It's kinda weird & convoluted.

The good news: This command set seems to cover nearly everything the WebUI does. Which means that you can do these things without hunting through a GUI. (You just get to hunt through this documentation instead... :| )

Usage

Usage: esxcli [options] {namespace}+ {cmd} [cmd options]

Options:
  --formatter=FORMATTER
                        Override the formatter to use for a given command. Available formatter:
                        keyvalue, csv, xml
  --debug               Enable debug or internal use options
  --version             Display version information for the script
  -?, --help            Display usage information for the script

The NameSpaces

device

Device manager commands

esxcli

Commands that operate on the esxcli system itself allowing users to get additional information.

fcoe

VMware Fibre Channel over Ethernet (FCoE) commands.

graphics

VMware graphics commands.

hardware

VMKernel hardware properties and commands for configuring hardware.

iscsi

VMware Internet Small Computer Systems Interface (iSCSI) commands.

network

Operations that pertain to the maintenance of networking on an ESX host. This includes a wide variety of commands to manipulate virtual networking components (vswitch, portgroup, etc) as well as local host IP, DNS and general host networking settings.