@KJK Yep there is one lagg containing multiple vlan's towards pfSense (ports 1 &2). One of those vlans (vlan17) is the vlan related to the PC. And the picture in my post above related to vlan17 shows...

@KJK Yep PIVD are essential to define the vlan for untagged devices. The default is one for each port and all devices are interconnected. Exactly what I do not want. I am not using "vlan-1". So the...

There is more which is not OK and that could be related. Here more starting with an outline from the situation. The picture shows the router.firewall pfSense attached to a 1G-network below a Zyxel...

Problem I know there is an earlier thread with this name. However even with significant knowledge an many hours spend, I did not manage the pfSense IPV4-DHCP-server to hand out an address to a PC...