I host all my stuff with Hetzner (who are at the cheap end of the market compared to Softlayer) and even they provide pre-configured VLANS and private switches.

I host all my stuff with Hetzner (who are at the cheap end of the market compared to Softlayer) and even they provide pre-configured VLANS and private switches. For intra-DC you can just setup some redundant openvpn links or pay the dc to configure a hardware tunnel between both sites.