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.
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Description

This article explains how to maintain physical layer 2 ethernet connectivity when running in bypass mode on the FortiGate. This article applies to the following FortiGate devices:-

FortiGate 100D-rev 2
FortiGate 600C
FortiGate 800C
FortiGate1000C

Scope
FortiOS v4.0

Solution
The below ASCII diagram shows when using bypass ports there has to be 1 (or an odd number) of cross-over ethernet cables in the layer-2 path. Therefore when a pair of ports fail-over in bypass mode, connectivity is maintained :-
 
 
NB :-In this example bypass mode is running between 3 FortiGate devices FortiGate 51B, 1000C, and 311B, the cross over cable should be cabled between switch1/port 17 and the FortiGate 1000C/wan1 interface. 
 
 
This information does not apply to the standalone FortiBypass appliances.
 
 
FGT51B(wan1)--(port16)--switch1--(port17)--(wan1)--FGT1000C--(port1)--(port16)--switch2--(port17)--(port1)--FGT311B

 

switch1 : port16 and port17 belong to vlan111          VLAN0111                         active    Fa0/16, Fa0/17

 

switch2:  port16 and port17 belong to vlan222          VLAN0222                         active    Fa0/16, Fa0/17 
 

Related Articles

Technical Tip: FortiGate Bypass interfaces

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