Description
This article explains how to specify more than one DHCP relay IP, to allow for the coverage of additional LAN subnets.
It is possible to set up to 8 IPs from the CLI.
Scope
FortiGate.
Solution
In the FortiOS GUI, navigate to Network -> Interfaces -> Interface_NAME.
In the GUI interface view, under the DHCP Ranges column, the DHCP scope and the DHCP relay server IP can be viewed.
Via CLI:
config system interface
FGT (interface) # edit port2
FGT (port2) # set dhcp-relay-service enable
FGT (port2) # set dhcp-relay-ip 1.1.1.1 2.2.2.2 3.3.3.3
FGT (port2) # next
FGT (interface) # end
FGT (interface) # edit port2
FGT (port2) # set dhcp-relay-service enable
FGT (port2) # set dhcp-relay-ip 1.1.1.1 2.2.2.2 3.3.3.3
FGT (port2) # next
FGT (interface) # end
Debug command for DHCP relay:
diagnose debug application dhcprelay -1
To enable sending of DHCP requests to all configured DHCP servers (default setting is 'disable') :
config system interface
FGT (interface) # edit port2
FGT (port2) # set dhcp-relay-request-all-server enable
FGT (port2) # next
FGT (interface) # end
FGT (interface) # edit port2
FGT (port2) # set dhcp-relay-request-all-server enable
FGT (port2) # next
FGT (interface) # end
Note:
If multiple DHCP Relays are configured, the FortiGate will send the requests to all the DHCP servers configured in the relay settings and the client will accept an offer from the first DHCP server to reply.
Related document:
