@TommyYap the idea of VLANs is to separate the network into logical zones as I think you wish to do. Initially if you enable VLANs but leave everything in VLAN 1 then all your existing devices should continue to work as they do now. If you create a second VLAN then you will need to create a VLAN interface in both the original VLAN1 and the new VLAN. This allows devices in each VLAN to talk to each other. As an example the IP addressing could be as below:
Original network: 192.168.0.0/24
New VLAN1: 192.168.0.0/24 <- the same as above
New VLAN1 interface IP: 192.168.0.1
New VLAN2: 172.18.0.0/16
New VLAN2 interface IP: 172.18.0.1
Default route of 0.0.0.0/0 192.168.0.254 (IP address on MX in VLAN1)
A device on VLAN1 would have an IP address of 192.168.0.n with a subnet mask of 255.255.255.0 and a gateway of 192.168.0.1
A device on VLAN2 would have an IP address of 172.18.n.n with a subnet mask of 255.255.0.0 and a gateway of 172.18.0.1
To access the internet a device on VLAN2 would go to the L3 device (MS) and then onto VLAN1 and out through the MX.
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