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jprocha
Explorer II
October 22, 2024
Solved

Remove VLANs from Fortiswitch ISL Trunk

  • October 22, 2024
  • 1 reply
  • 1256 views

Hello everyone!

 

I would like to know if there is a way to exclude specific VLANs from passing inside a fortiswitch ISL trunk or to pass only management traffic between a specific ISL link.

 

By default fortilink passes all VLANs between Fortiswitches connected to each other. Yet, I have a requirement to not allow specific VLANs to pass through a ISL formed between 2 FortiSwitches, therefore forcing data traffic to go through a 3rd party switch connected to both of these Fortiswitches.

 

KB: https://community.fortinet.com/t5/FortiSwitch/Technical-Tip-Seperate-Inter-Switch-Link-ISL-between-Managed/ta-p/224568
states about separating the traffic, but my requirement does not need the second link to pass data. Is there a simpler way to achieve this? Did not want to go into modifying MSTP instances and all of that.

 

Thanks in advance for any suggestions and tips!

 

Regards

 

FortiSwitch 

Best answer by ebilcari

This article shows how to make static ISL for Fortlink trunk and manually select the allowed VLANs and may work also for ISL between switches. You can also remove auto-isl and manually configure trunks. If you have a pair of spare switches you can test it.

1 reply

ebilcari
Staff
ebilcariAnswer
Staff
October 22, 2024

This article shows how to make static ISL for Fortlink trunk and manually select the allowed VLANs and may work also for ISL between switches. You can also remove auto-isl and manually configure trunks. If you have a pair of spare switches you can test it.

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