Check addressing mode if HA cluster not setting up properly


If you appear to have configured your HA settings correctly but after trying to implement the HA cluster everything is still in stand-alone mode the issue could be with the interfaces.

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:

  1. Go to System > Network > Interface
  2. Select the interface to edit, for example: wan1
  3. Set the Addressing mode to “Manual
  4. 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>

Scope of issue

This issue affects FortiOS version 5.0 but not 5.2. The limitation that causes the issue was removed in 5.2 for FGCP (FortiGate Clustering Protocol).

Bruce Davis

Bruce Davis

Technical Writer at Fortinet
Bruce has been working with computers, and related technology, since before the World Wide Web was a thing. He has worked in system and network administration. He has even dabbled in technical support. He has made the switch to technical writing as part of his deep, dark and dastardly plan to make the arcane machinations of IT technology more easily understood by the poor folks who use it.
Bruce Davis

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