Thanks for your reply  @Clive_A 

Here's a bit of a sketch of the network - it's more complicated than this, but hopefully will paint the picture:

All the access points have a trunk that contains VLANs except the WAN VLANs. They broadcast a number of SSIDs, one for each VLAN. There are also other devices on each switch connected to each VLAN.

The routing is working between the LAN VLANs and I understand I can use ACL to limit routing between VLAN interfaces. But I'm confused about the WAN side of things - eg VLAN 3. I don't know whether for the purposes of the Omada router it is just another LAN VLAN or it needs to be setup differently as a WAN interface?

If the Omada router was connected directly to the starlink router, I'd connect it to the WAN port on the Omada router and set it to be a DHCP client, the starlink router would assign it an IP address and upstream DNS servers etc. But with the switches and VLANs in between I'm confused how to set this up in Omada?

When I set this up on my OpenWRT router, I still have a WAN interface getting assigned an IP address by the Starlink Router, just with VLANs passing this across the switches. I just don't know how to achieve the same with Omada.

Thanks

Thanks for taking a look  @Clive_A 

Just to respond to a couple of your comments there
 

For the VLAN setup, you should set up the VLAN 101 110, and 111 on the router's LAN. Trunk the LAN port and it will pass the traffic to the SG1210MPE. You should do the VLAN trunk on the following switches as well.

This is what I have done and the LAN side seems fine

For what's confusing to me is that your OpenWRT. If the diagram shows your network, then I assume 707-M2 is in the place where your OpenWRT sits, so if you are gonna replace it, do what's on the OpenWRT already and see if it can inherit the configs of OpenWRT.

That'd be the easiest way and you don't have to rearrange your network.

That's correct, the OpenWRT router is currently sitting where the 707-M2 is shown.

What do you mean do what's on the OpenWRT? How can it inherit the configs? This is essentially what I'm trying to do and struggling with - how to replicate the settings - the Omada interface is completely different.

This is some untraditional setup and I have no experience with it. I cannot give you suggestions or steps in this.

Possibly untraditional, but I think it's a fairly common router-on-a-stick setup? I could be wrong. Hopefully the issue is just the way I'm asking the question.

Basically there are 2 WAN modems at the site, a 4G modem/router and the starlink. They are physically located in different buildings due to aerial/dish placement for each so I can't physically/directly connect the 707 to both of them at the same time - it needs to pass one of the WAN connections across the switches as a VLAN - this is what I'm trying to achieve - there is only a single ethernet cable between the buildings so the WAN traffic needs to share this trunk cable with the LAN traffic.

Essentially my question is: how can I configure the Omada router to use a WAN connection when the modem/router is not able to be directly connected to the WAN port - how can it make use of a trunk connection and VLAN to access the WAN modem/router?

If you can't help me (and I appreciate you trying, thanks), hopefully someone else on here has some experience with doing this?

If I cant do it within the Omada router config I'm thinking I will run a second cable from WAN port on router to the switch and do the WAN->VLAN mapping there - hopefully that will work