Is it possible to set up the uplink network which the MS390 use to communicate with the cloud for participation in the OSPF routing domain?
I tried setting up another IP on the same subnet/VLAN under "Routing & DHCP", this newly created interface cannot reach anything, not even the mgmt IP of the MS390 itself. Is there some VRF going on under the hood? I tried this because the mgmt subnet cannot be configured for OSPF participation otherwise.
I'm guessing I have to set up the mgmt/cloud uplink outside of the OSPF process with the subnet terminating in a border device?
Hey, these are good questions. Your L3 switch or switch stack will need to have it's management IP within the uplink subnet with a default gateway that is routable to the internet. This does NOT mean that it cant be in the same L3 segment, but you have to have a control plane MGMT IP & Data-plane IP. Example.
Northbound uplink is 10.0.0.0/29.
Neighbor is 10.0.0.1
switch SVI is 10.0.0.2 and default static is 10.0.0.1
switch management is 10.0.0.6 and default gateway is 10.0.0.1
You can absolutely peer with 10.0.0.1 using OSPF for dynamic routing, but the management interface (10.0.0.6) must be able to statically point to 10.0.0.1 and reach the internet.