When setting up an HA cluster it is important to make sure that none of the interfaces are configured to get their IP addresses from a DHCP server. Each interface should bestatically assigned. If any of the interfaces in an HA cluster are set to obtain dynamically assigned addresses the cluster will not work. This includes addresses from PPPoE as well as DHCP.
Some FortiGate units have DHCP as the default addressing method for some of the interfaces, so it pays to take a few extra moments to check. Setting the interface addressing mode.
In the Web Based Manager:
- Go to System > Network > Interface
- Select the interface to edit, for example: wan1
- Set the Addressing mode to “Manual”
- Enter the IP address and mask in either the:
- IP/Network Mask field
- IPv6 Address field
If you prefer to work in the CLI…
Open up a terminal window and log in to the FortiGate unit.
Use the following commands:
config system interface edit wan1 set mode static
For IPv4 addresses:
set ip <include address and mask>
For IPv6 addresses:
config ipv6 set ip6-address <IPv6 address>