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New Contributor III

Bandwidth between VLANs


We have a Fortigate 30E and a Zyxel GS1900 Switch in our office.

We recently created a new VLAN (192.168.3.x) and put all our servers and NAS in this VLAN.

Our office PC remains in the original VLAN (192.168.0.x).


My colleagues report that after changing the NAS to the new VLAN,  the connection speed seems to be lower than before.


Is there a bandwidth limitation between VLANs inside Fortigate that causes it?

Or since we have only one RJ45 cable between Fortigate and switch, do we need to use two ports and link aggregation bebetween Fortigate and switch to improve bandwidth limitation between VLANs?


Can you advise us what could cause this low connection speed problem and how to solve it?

Thank you.


New Contributor

The type of QoS you are talking about is usually done on the router end where you can specify protocols or ip addresses of the devices you want to shape traffic for. VLANs are more to segregate traffic. I mean yeah you can put devices on separate subnets on the switch and then have a router QoS basing on the subnet.

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