1.dhcp lease-list

exec dhcp lease-list –> show current list on DHCP lease
execute dhcp lease-clear <ip_addres> –> clear the DHCP lease of a specific ip
execute dhcp lease-clear all —> clear all the DHCP leases

2.Fortigate Static NAT Configuration
http://www.jaringankita.com/blog/fortigate-static-nat-configuration

3.Fortigate 110c Factory

3-1.Baud 9600 （serial port com1 or com2）

3-2.CLI

1) Open a SSH to the system and execute the following command:

exec factoryreset 

2) A warning will appear.

This operation will reset the system to factory default!
Do you want to continue? (y/n)

3) System will reboot and will load a basic configuration.