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New Member

VLAN IP address

hi all, may i ask something on VLAN IP address.


is it necessary to assign IP address to VLAN beside you need to do routing on Layer 3  ?

Say i create Vlan 192 => 192.168.1.x /24

All the servers uses static IP. I have a load balancer assign as


If i assign the IP range to Vlan 192, there will be a log about mac address duplication.


So do I change the Vlan IP to instead ?


is there any implication ?


Hall of Fame Super Blue

If you do not assign an IP to

If you do not assign an IP to the L3 vlan interface (SVI) for that vlan then you cannot route that vlan.

You can assign any IP from the subnet range to the SVI.

It's not clear exactly what you are asking though. You have a load balancer using, is that device in vlan 192 ?


New Member

Yes the LB is in same Vlan

Yes the LB is in same Vlan 192. I guess I got the duplicate error when i assign Vlan 192 as




Hi, The implications are that



The implications are that any devices which live on that vlan + want to route traffic to a different subnet, need to be configured with the svi ip address as their default gateway. i.e. if you change the svi ip address without changing the host's default gateway address, you will stop these hosts from reaching remote destinations..


Please excuse me if I have not understood your requirements properly.





Helloif you mean having these


if you mean having these devices in that specific ip range just connect to each other then there is no need for a L3 vlan, they just need to be in the same L2 vlan.

But as Jon stated if you need these devices to connect to other vlans then you will need a l3 interface  be it an SVI on a L3 switch or a router to perform the routing.




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