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Potato168
Explorer
December 9, 2024
Question

Question regarding Firewall Active-Active Layer 2 HA design

  • December 9, 2024
  • 6 replies
  • 2038 views

Hello all,

 

I have a question regarding a design like this.

 

Suppose CheckPoint A is the Master unit for its cluster, while Forgate A and B are in Active-Active HA.

 

Fortigate A or B comes with one virtual wire and the VW1 is connected between the Checkpoint and Core switch.

 

No switch is between Fortigate and Checkpoint.

 

I wonder if Fortigate B receives traffic from a user, can the user stillbe able to use CheckPoint A to access to the internet?

 

 

Design.PNG

6 replies

sjoshi
Staff
Staff
December 9, 2024

Hi,

 

Is there any connection between FGTB and checkpoint A or FGTB is only connected to checkpoint B?

Also in checkpoint is it working as Active-Passive mode? 

Thanks, Salon
Potato168
Potato168Author
Explorer
December 16, 2024

No  connection between FGTB and checkpoint A . Only A to A and B to .

Checkpoint is it working as Active-Active - Clueter mode.

AEK
SuperUser
SuperUser
December 9, 2024

Hi Potato

I don't think it will work like that, because the FG Master may not see the CheckPoint Master.

Even in AA-HA, FG master is the one who receives the incoming traffic, so you need a switch between the two firewall clusters.

AEK
jakbork
Visitor III
December 9, 2024

I will also try your advice. Thank you.

sjoshi
Staff
Staff
December 9, 2024

This article describes an example of a simple TCP 3-way-handshake in HA Active-Active cluster where packet distribution between Master and Slave FortiGate occurs.
Refer:-
https://community.fortinet.com/t5/FortiGate/Technical-Tip-FortiGate-HA-A-A-cluster-3-way-TCP-handshake/ta-p/197467

Thanks, Salon
Potato168
Potato168Author
Explorer
December 17, 2024

So, what if got drop on Step 3 ?

3) SYN is forwarded from internal interface to External Interface to the external switch connected to the Server

Will the Master FG1 try to resend SYN forward to the Server?

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