Overlay networks

Overlay networks are industry-standard techniques designed to achieve Network Virtualization. Network Overlays such as Virtual eXtensible Local Area Network (VXLAN) and Generic Routing Encapsulation (GRE) achieve network virtualization by overlaying layer-2 networks over physical layer-3 networks, which enables network scalability and the efficient use of current network infrastructure.

Open vSwitch supports multiple tunneling protocols (GRE, VXLAN, STT, and Geneve, with IPsec support), which allow scaling private networks over public networks. You can connect two or more Open vSwitches running on different hosts with each other and form a distributed switch.

Use Case of overlay networks: Suppose you have an application cluster (five VMs serving as nodes) on the KVM1-Mumbai-DC host, The cluster is architectured on a private network that is isolated to the host, The recent growth of your application requires more nodes on the cluster but you found there is no scope to create...