I ran into the same issue as described by Eric Sloof:
https://www.ntpro.nl/blog/archives/3570-Edge-Tunnels-Down-when-hosting-NSX-T-on-the-same-DVS.html
The problem I had was i did not have enough uplinks to create a new dvSwitch to get the tunnel to work.
For the tunnel to work, the geneve traffic has to leave the host and get routed back in.
I had a layer 3 physical switch and decided to make use of inter-vlan routing.
Once logged into the switch:
1. Enable ip routing
console(config)#ip routing
2. Create an SVI(Switch Virtual Interface) for each vlan
console(config)#interface vlan 50
console(config)#ip address 172.1.1.1 255.255.255.0
console(config)#interface vlan 60
console(config)#ip address 10.1.1.1 255.255.255.0
3. You can further restrict ip routes using ACLs
Login to NSX-T
1. System->Fabric->Profiles->Uplink Profiles: Ensure the correct transport vlan is configured for the overlay uplink profile and the edge overlay uplink profile. In my case, vlan 50 and vlan 60.
2. Networking->Ip Address Pools->Add/Edit overlay TEP ip address pool->Subnets-> Ensure the gateway is specified. In my case 172.1.1.1
3. Networking->Ip Address Pools->Add/Edit Edge TEP ip address pool->Subnets-> Ensure the gateway is specified. In my case 10.1.1.1
4. System->Fabric->Nodes->Edge Trasnport Nodes->Edit/Add Edge->Ensure the correct transport zone and the Edge TEP ip pool is selected.
