Hello!

A short description, from a cisco 2960 i've tried created a trunk carrying 3 vlans(200/500/600) and vlan 1 as native.

For starters i configured the tp-link to include all ports on all vlans as untagged just to get it upp and running but a soon as i activated the trunk on the cisco the tp wont connect anymore. It indicates that it is connected but neither the switch ip or any devices connected to it are reachable.

After that i went into troubleshooting, firstly just enabling the port on the cisco as a normal vlan-port cycling through the vlans and in that case the tp connected.

Made sure dot1q encapsulation was active and as the cisco only is able to use the dot1q i also ruled that out.

The next thing i did was to only allow VLAN 1 on the trunk and use that as a native and the tp connects fine.

So status at this point is, port connected to the tp on the cisco is configured as trunk, VLAN 1 is the only one allows and is native.

Now i tried to allow another vlan(200) on the trunk and the tp immediately takes a dive and wont connect, if i remove 200 from allowed the connection goes back up again.

Also tried only allowing another VLAN ie 200 and setting that as native on the cisco but the tp doesnt connect in that case either.

Any help in this matter are appreciated as im somewhat stuck.