FortiGate
FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
donghee
Staff
Staff
Article Id 410411
Description

This article describes that in a FortiGate environment with the HA Direct feature enabled, sensitive authentication traffic is properly routed through a dedicated MGMT (management) interface, while other LDAP query traffic (e.g., periodic user synchronization) attempts to communicate through a service interface (e.g., x1).

Scope FortiGate.
Solution

Symptoms.

  • The ha-direct feature is enabled on a FortiGate HA cluster.

  • When an administrator logs in, LDAP traffic is routed through the MGMT interface.

  • Background LDAP processes initiated by the FortiGate (e.g., user synchronization or status checks) try to communicate via a regular service interface.

 

Cause.

This behavior is normal and occurs because FortiGate routes traffic depending on whether it's for an authentication task or not.

 

Authentication traffic for administrative access is routed via the MGMT interface based on the ha-direct priority. This ensures management access regardless of the HA cluster's status.

 

Other LDAP query traffic, like periodic background processes initiated by the FortiGate, does not follow the ha-direct priority and instead uses the regular routing table, which sends it out through a service interface.

 

If FortiGate only needs to query the LDAP server during a login event:

Disable the user-info function in the LDAP server object to stop periodic LDAP queries.

In the user LDAP, use the following command:

 

config user ldap

    edit "LDAP-Server-Name"

        set user-info disable

    next

end

 

This setting will cause the FortiGate to query the LDAP server only when a login event occurs, reducing background traffic.

 

Note:

If user-info is kept enabled (the default), administrator authentication will still function correctly even if traffic leaving the service interface is ignored.

 

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