Two VLANs sharing uplink cable
Hi, I have tested a setup that I need to deploy into a data centre which works fine apart from the VLANs route to each other if sharing an uplink cable….this involves a layer 3 HP procurve (no routing setup) with 3 vlans, then cable uplinks to a spare WG XTM510 optional for two vlans and one to trusted for the third management vlan1. In production this will be a M200.
so switch has;
switch VLAN1 default management > cable to trusted > devices use 10.0.1.0/24 GW Trusted 10.0.1.1 DHCP on
switch VLAN20 servers > switch uplink cable tagged both vlans (both vlan20/30 use) to VLAN port on WG optional eth6 – devices use 192.168.30.0/24 GW optional eth6 VLAN20 192.168.30.254 with DHCP. Trusted security zone.
switch VLAN30 servers > switch uplink cable tagged both vlans (both vlan20/30) to VLAN port on WG optional eth6 – devices 10.80.80.0/24 GW optional eth6 VLAN30 10.80.80.254 with DHCP. Trusted security zone.
This all works fine, no vlan IPs or routing on the switch needed as the WG is doing that, but by default VLANs 20 & 30 can connect to each other as they share a cable and zone. I don’t want this to happen, so how can I separate the VLANs 20 and 30 “if sharing the same cable uplink to the WG”, or do I need an uplink per vlan? Or is it the security zones need changing on the optional port? Three outgoing rules on the WG, one per VLAN to external.
Everything, incoming sNATs etc and outgoing all works fine, I just need to stop the vlans 20 and 30 talking to each other. Hopefully I have explained this well enough.