Technical Tip: How to add unique DHCP lease time for specific IP range

[Mohammed_Feroz]

Description	This article describes how to add a unique DHCP lease time to a Specific IP range under the same DHCP server.
Scope	FortiGate v7.2.4 onwards.
Solution	There might be a requirement where a specific set of IP ranges needs a higher DHCP lease time, and others need a lower DHCP lease time under the same DHCP server. In the below example:   The DHCP server has a global lease time of 7 days (604800 seconds, 0 seconds means unlimited). DHCP lease time can be specified with a Minimum value of 300 Seconds and a Maximum value of 8640000 (100 days). The first IP range will use the global DHCP lease time. The second IP range will use 1 hour (3600 seconds) as its DHCP lease time (only available over CLI). config system dhcp server     edit 2         set dns-service default         set default-gateway 172.31.205.234         set netmask 255.255.240.0         set interface "port3"             config ip-range                  edit 1                      set start-ip 172.31.192.2                      set end-ip 172.31.207.10                  next                  edit 2                      set start-ip 172.31.207.11                      set end-ip 172.31.207.20                      set lease-time 3600                  next              end     next end