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.
kcheng
Staff & Editor
Staff & Editor
Article Id 222558
Description

This article illustrates the issue where the connection status to AD is successful, but the AD connector status is down.

 

kcheng_0-1662019120375.pngkcheng_1-1662019175278.png

 

The connector settings are configured as below:

 

kcheng_3-1662019410593.png

 

It is possible to run debug to check for the error message:

 

diagnose debug application fssod -1

diag deb en

 

An error message appears for 'wrong format of data status, len 8 <> 4'.

 

Although, it is possible to see that the authentication is successful:

 

kcheng_4-1662019502060.png
Scope FortiGate, FSSO Polling mode.

Solution

The username in FSSO Connector Settings should not include the domain. Once the domain portion was removed from the Connector Settings, the domain was removed:

 

kcheng_5-1662019600304.png

 

Turn on the debug to verify if the connection is proceeding accordingly:

 

kcheng_6-1662019728711.png

 

Based on the above debug log, it is possible to see that the LOGON info is correctly transmitted. FortiGate GUI is also showing that the connector connectivity is up and successful:

 

kcheng_7-1662019833099.png

 

If still seeing the error message: wrong format of data status, len 8 <> 4'

 

Run a pcap either on the GUI or on CLI:

 

diagnose sniffer packet any "host <DC IP> and port 445" 6 0 a

 

Check the PCAP for errors similar to those shown below:

 

PCAP.PNG

 

There is a built-in AD group 'Event Log Readers', make sure the user (tadmin here) is a member of the group to have read and polling access on the DC.


Note:

If the issue persists, verify if the SAMBA service is running in the DC as it is required for polling mode. If not, follow this document from Microsoft for verification: Detect, enable, and disable SMBv1, SMBv2, and SMBv3 in Windows | Microsoft Learn