Agent-based FSSO

Agent-based FSSO

FortiOS can provide single sign-on capabilities to Windows AD, Citrix, or Novell eDirectory users with the help of agent software installed on these networks. The agent software sends information about user logons to the FortiGate unit. With user information such as IP address and user group memberships from the network, FortiGate security policies can allow authenticated network access to users who belong to the appropriate user groups without requesting their credentials again.

For Windows AD networks, FortiGate units can provide SSO capability without agent software by directly polling the Windows AD domain controllers. For information about this type of SSO, seeSingle Sign-On to Windows AD on page 545.

The following topics are included:

  • Introduction to agent-based FSSO
  • FSSO NTLM authentication support
  • Agent installation
  • Configuring the FSSO Collector agent for Windows AD
  • Configuring the FSSO TS agent for Citrix
  • Configuring FSSO with Novell networks
  • Configuring FSSO Advanced Settings
  • Configuring FSSO on FortiGate units
  • FortiOS FSSO log messages
  • Testing FSSO
  • Troubleshooting FSSO


Introduction to agent-based FSSO


Fortinet Single Sign-On (FSSO), through agents installed on the network, monitors user logons and passes that information to the FortiGate unit. When a user logs on at a workstation in a monitored domain, FSSO

  • detects the logon event and records the workstation name, domain, and user,
  • resolves the workstation name to an IP address,
  • determines which user groups the user belongs to,
  • sends the user logon information, including IP address and groups list, to the FortiGate unit
  • creates one or more log entries on the FortiGate unit for this logon event as appropriate.

When the user tries to access network resources, the FortiGate unit selects the appropriate security policy for the destination. If the user belongs to one of the permitted user groups associated with that policy, the connection is allowed. Otherwise the connection is denied.

FSSO can also provide NTLM authentication service for requests coming from FortiGate. SSO is very convenient for users, but may not be supported across all plat- forms. NTLM is not as convenient, but it enjoys wider support. See FSSO NTLM authentication support on page 559.

Introduction to FSSO agents

There are several different FSSO agents that can be used in an FSSO implementation:

  • Domain Controller (DC) agent
  • eDirectory agent
  • Citrix/Terminal Server (TS) agent
  • Collector (CA) agent

Consult the latest FortiOS and FSSO Release Notes for operating system compatibility information.


Domain Controller (DC) agent

The Domain Controller (DC) agent must be installed on every domain controller if you will use DC Agent mode, but is not required if you use Polling mode. See FSSO for Windows AD on page 555.


eDirectory agent

The eDirectory agent is installed on a Novell network to monitor user logons and send the required information to the FortiGate unit. It functions much like the Collector agent on a Windows AD domain controller.The agent can obtain information from the Novell eDirectory using either the Novell API or LDAP.


Citrix/Terminal Server (TS) agent

The Citrix/Terminal Server (TS) agent is installed on a Citrix terminal server to monitor user logons in real time. It functions much like the DC Agent on a Windows AD domain controller.


Collector (CA) agent

This agent is installed as a service on a server in the Windows AD network to monitor user logons and send the required information to the FortiGate unit. The Collector agent can collect information from

  • Domain Controller agent (Windows AD)
  • TS agent (Citrix Terminal Server)

In a Windows AD network, the Collector agent can optionally obtain logon information by polling the AD domain controllers. In this case, DC agents are not needed.

The Collector can obtain user group information from the DC agent or optionally, a FortiGate unit can obtain group information directly from AD using Lightweight Directory Access Protocol (LDAP).

On a Windows AD network, the FSSO software can also serve NT LAN Manager (NTLM) requests coming from client browsers (forwarded by the FortiGate unit) with only one or more Collector agents installed. See FSSO NTLM authentication support on page 559.

The CA is responsible for DNS lookups, group verification, workstation checks, and as mentioned FortiGate updates of logon records. The FSSO Collector Agent sends Domain Local Security Group and Global Security Group information to FortiGate units. The CA communicates with the FortiGate over TCP port 8000 and it listens on UDP port 8002 for updates from the DC agents.

The FortiGate unit can have up to five CAs configured for redundancy. If the first on the list is unreachable, the next is attempted, and so on down the list until one is contacted. See Configuring FSSO on FortiGate units on page 586.

All DC agents must point to the correct Collector agent port number and IP address on domains with multiple DCs.

A FortiAuthenticator unit can act much like a Collector agent, collecting Windows AD user logon information and sending it to the FortiGate unit. It is particularly useful in large installations with several FortiGate units. For more information, see the FortiAuthenticator Administration Guide.


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