Quick guide / cheatsheet with various ESXCLI commands specifically for ESX 7.0+

Enter maintenance mode:

esxcli system maintenanceMode set --enable true

Exit maintenance mode:

esxcli system maintenanceMode set --enable false

Restart management agents “ESXi host daemon” and “vCenter Agent” services:

/etc/init.d/hostd restart

/etc/init.d/vpxa restart

Restart management agents “All”:

services.sh restart

Reboot Host:

esxcli system shutdown reboot --reason Upgrades

Reference: 

Restarting the Management agents in ESXi (1003490) (vmware.com)