and if you have more than one? or more than one dc?
somebody needs to connect it, or you will need a VPN.
it's not that easy without Clouds if you need connected servers.
We switched to AWS since connecting servers in a dc isn't as cheap as people think of.
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.
We get free inter-DC connectivity for free with Softlayer. There really is no difference for us between connecting to a server within a DC or between datacenters (aside from added latency, of cource) – the same private address space, the same access rules (we see all of our machines in a private backend network from any datacenter).
This article was talking about renting servers from Softlayer. All servers on your account in Softlayer have a private VLAN that connects them, even between data centers. Private networks for your servers are a feature of many server hosts.
