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retsam
Visitor III
May 15, 2023
Question

Fortiswitch stack

  • May 15, 2023
  • 2 replies
  • 9305 views

Hello i know that the fortiswitches can be managed in stand alone

 

As far i know there are fortiswitches that can be L3 switches, but can they stack? 

Right now we have a client that have switches of another brand which are stacked, but the client does not have a fortigate yet.  They plan to have fortigates but that will be later.

We would like to stack 2 switches, so they can do a normal Link aggregation between the switches of the other brand with the fortiswitch like  for example:

 

a stack of a Fortiswitch of 2 switches

 

and having a link of a cisco switch that goes to the port 48 of each fortiswitch in LACP

 

Is that possible with forti switch?

 

If its not possible what could be an alternative?

 

Thanks

2 replies

AEK
SuperUser
SuperUser
May 16, 2023

Hello Retsam

FortiSwitches can be stacked and LACP can then be configured from stacked switches.

You can check datasheet and admin guide for official ref.

You may need to check if it has a limited number of LACPs when switches are stacked (usually some other constructors have a limit).

 

LACP is standard, so it should work between FSW & CISCO.

 

AEK
gfleming
Staff
Staff
May 16, 2023

It is not possible. FortiSwitch stacking is basically STP  ring topology. No LACP split between switches.

 

You can do MC-LAG which allows LACP to span across two fortiswitches but you need to have models 2XX or higher to support this (doesn't work on 1XX models).

 

To keep it simple you can just have links from port 48 of each fortiswitch to the cisco switch stack and one link will be blocked by STP.

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