SG200 - VLAN trunk - simple configuration to pass VLAN tagged traffic?

[timg11]

I'm using a single VLAN to isolate guest network traffic between Ubiquiti AP's and the gateway router (Ubiquiti ER-X). 

If an AP is cabled directly into a port on the router, the private network and guest network work fine.

When the AP is connected through the SG200 switch, traffic tagged as VLAN is not passed, and the guest network does not function.

In the SG200 (firmware v1.4.2.4), VLAN Management, Interface Settings, every interface VLAN mode is set to Trunk.

I thought "Trunk" means the interface will pass all traffic tagged or untagged, but apparently that is not the case.

Default VLAN ID is 1.  There are no other VLANs listed under VLAN Settings except 1.

In the Port to VLAN table, all interfaces are membership type "Untagged"

What is the configuration change necessary to allow VLAN tagged traffic to pass through the switch?

[Georg Pauwen]

Hello,

why do you need a trunk when you only use the default VLAN ?

[timg11]

I need to configure settings so that specific interfaces will pass default (untagged) as well as VLAN tagged traffic.

The default settings (with interfaces as Trunk) do not pass the VLAN tagged traffic.

[timg11]

I want the switch to simply pass VLAN tagged traffic, without adding or removing any tags. In effect, it should behave as an unmanaged switch.

In VLAN settings, I have the default VLAN 1, and I have created VLAN 100.

In Port to VLAN, VLAN 1, every port is set to untagged

In Port to VLAN, VLAN 100, every port is set to excluded by default. How do I set the ports with AP's to pass VLAN tagged traffic, but not affect the tags?  Tagged or Untagged?

This article says:

• Tagged — The interface is a member of the chosen VLAN and packets sent from this interface destined to the chosen VLAN will have the packet tagged with the VLAN ID. The Tagged radio button is not enabled for interfaces in Access mode if the chosen VLAN is the Default VLAN. If there are no untagged VLANs on an interface, the interface automatically joins the internally used VLAN 4095.
• Untagged — The interface is a member of the chosen VLAN and packets sent from this interface destined to the chosen VLAN will not be tagged with the VLAN ID. If the interface is in Access or Trunk mode, the Default VLAN is automatically excluded when the interface joins the VLAN as Untagged.

Tagged doesn't sound right because it says "will have the packet tagged with the VLAN ID". The packets are already tagged, and just need to be passed through.

Untagged seems to have the undesired side effect of "the Default VLAN is automatically excluded"

[timg11 · Accepted solution]

I selected "Tagged" for the ports connected to the APs. That seems to work. VLAN traffic is passed, as well as untagged traffic.