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.
tonylin1
Staff
Staff
Article Id 228871
Description This article describes how to force the syslog using specific IP address and interface to send out to Internet.
Scope If the FortiGate has a default route on WAN1, but to send the syslogd by LAN IP address to Internet.
Solution
  1. Create syslogd settings as below:

config log syslogd setting
    set status enable
    set server "x.x.x.x" <----- IP Address in internet.
    set source-ip "14.14.14.9" <----- IP Address of LAN.
    set interface-select-method specify
    set interface "lan"
end

 

From the web interface (GUI), it is also possible to configure these settings:
By default Local Out Routing is not visible in the GUI. Go to System -> Feature Visibility to enable it
 
Enable Local.PNG

 

Screenshot 2024-12-04 143926.jpg
 
From here, configure the Source IP, outgoing interface for 'Log Syslogd Setting':
 

syslogd.PNG

 

SYSCLOGD.PNG

 

  1. Add a default static route with higher priority:

 

# get router info routing-table all
Codes: K - kernel, C - connected, S - static, R - RIP, B - BGP
O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default

Routing table for VRF=0
S* 0.0.0.0/0 [10/0] via y.y.y.y, wan1, [1/0]
[10/0] via 14.14.14.14, lan, [1/0]

 

  1. It is possible now to see that the syslog traffic is sent out by the LAN IP and interface.

 

# diagnose sniffer packet any 'host x.x.x.x' 4 0 l
interfaces=[any]
filters=[host x.x.x.x]
2022-11-04 09:52:22.365267 lan out 14.14.14.9.4291 -> x.x.x.x.514: udp 560
2022-11-04 09:52:22.544854 lan out 14.14.14.9.4291 -> x.x.x.x514: udp 560
2022-11-04 09:52:25.424974 lan out 14.14.14.9.4291 -> x.x.x.x.514: udp 560