VLAN connectivity issue

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VLAN connectivity issue

I have configured my MX100 on a new network for an installation where we are going to migrate from an existing network and configured a connection between the new and the old networks.


However, with the way this is currently configured, all network traffic from the old network is appearing on the new network. Ideally we need these to be kept separate, so all devices connected on the new network have the ability to speak to hosts on the old network, but broadcast traffic and general network comms from the old network are not present on the new one.


The current setup has VLANs enabled and subnets added for the old ( VLAN 1) and the new network ( VLAN 101) and the old network is configured with an MX IP of a free address in that range ( 


The routing of the old network directs all traffic to to the MX IP configured on the old LAN.


Port 2 is connected directly to the Old LAN and configured with VLAN 1 on the per-port settings.

Port 3 is connected directly to the switches for the new network with VLAN 101 on the per port settings.


This allows connection between servers in both the old and new networks but also undesired network broadcast traffic from the old network across the new switches (visible in the Meraki logging and when using WireShark connected to the new switches).


I think I am just missing something obvious with regards to locking down the VLANs available on the switch ports? Or is there anything else I should be considering?


Thanks in advance.


1 Reply 1
Kind of a big deal
Kind of a big deal

If the MX (or MS) is connected to both networks, even if in different VLANs, the Meraki will will see the broadcasts from those other networks.  Nothing much you can do here.

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