I've been testing a switch with VLAN features. I have nothing configured on the router for VLANs because it does not support it.

I got it set up and was testing isolation between endpoints using ping. The endpoints seem to be horizontally isolated but not vertically, as in endpoint B (below the switch) can still communicate with endpoint A (in between the switch and router) or the other way around. Is this normal behavior with VLANs? Is there an option to prevent this vertical communication?

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  • 2
    VLANs divide a switch into multiple, virtual switches.. It takes a router to route packets between VLANs. Please edit your question to include the network device configurations.
    – Ron Maupin
    Jul 18, 2021 at 19:08
  • Also, in your diagram Endpoint A is on a routed port, separate from both VLANs 10 and 20.
    – Zac67
    Jul 19, 2021 at 4:28


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