Two parent NICs for VLAN

I have a physical switch with a number of VLANs and a NIC connected to a
wireless setup. I want to have those two separated except for one
particular VLAN that I want on the physical switch as well as on the APs.

So I have vmx1 connected to the APs and vmx3 to the switch.

Then some vlans that each has one of these as parents.

But then for VLAN 860, I want both vmx1 and vmx3 as parent... Can't they
have joint custody?

I could of course bridge vmx1 and vmx3 - but I only want vmx1 and vmx3
bridged for vlan 860. Does it make sense?

How to achieve this? Something similar to:








*vlan860: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu
1500 lladdr 00:0c:29:e0:88:9c description: IoT index
27 priority 0 llprio 3 encap: vnetid 860 parent vmx3 AND VMX1 txprio
packet rxprio outer groups: vlan media: Ethernet autoselect
(10GbaseT) status: active*

... which of coarse does not work.

Regards, Lars.