Hi,

I have an issue connecting two TL-SG108PE. My current setup looks like this

Switch 1 (TL-SG108PE v2):

Ports 1-4 are connected to Unifi APs, AP Management untagged, Regular Wifi VLAN2 tagged, Guest Wifi VLAN3 tagged.

Port 6 connects VLAN1 untagged to a larger unmanaged Switch

Port 7 connects VLAN3 untagged to Guest Network Uplink

Port 8 connects VLAN2 untagged to regular Internet. This setup works quite nice.

Now I needed to connect a 5th AP, so I got another TL-SG108PE - this time it was a Hardware Version V3.

I created the VLANs and set up the POE Ports 1-4 the same way - untagged1, tagged 2 and 3. Port 8 should be used as Uplink to the first Switch, so my setup looks like this:

Now I set up Port 5 of the first switch, to give VLAN 2 and 3 tagged to Switch 2:

At this point Switch 2 and everything connected to it is not reachable any more. It does not answer to pings, the webinterface is dead, etc. Which is highly confusing for me, as the untagged VLAN1 did not change at all...

I have set up a lot of VLAN setups but mostly with cisco devices - maybe I'm getting something wrong here, but I'm just not seing it. Thanks for any help!