Hi folks, I was checking some information regarding ACS advanced networking deployment mode, and I ran into this figure [1]. This made me wonder, what would happen with the following scenario.
Let`s say I have a similar scenario as the one depicted in figure [1], a set of pods with a set of clusters that have a set of hosts. Each host in a pod is linked directly using a Layer-2 switch. Let’s assume there exist network/aggregation layers that are configured properly and provide access to VMs in the cloud using the public IP net. Let’s also assume that the public IP net is 1.1.1.0/24; the management and storage networks are on isolated networks and are properly set up (Assume also that we are using the advanced networking mode). Now, I create a guest network 2.2.2.0/24. When I deploy a user VM, ACS will deploy a VR (let’s call x) with an IP (1.1.1.1) in the public net, and other on the guest network (2.2.2.1). Then, this VR(x) will execute the firewalling/forwarding for my newly created user VM. Let’s now imagine that I keep deploying user VMs to a point in which the POD gets full. The next VM I create ACS will have to deploy in other PODs of the environment. Because this new user VM will be in a different POD, the communication with other user VMs is not straightforward anymore (not a matter of using the same VLAN and net). What will ACS do to link users VMs that are on the same virtual network, but deployed in different PODs? Will it deploy other VR(y) with an IP (let's say 1.1.1.2) on the new POD and create a route between VR(x) and VR(y) using the public network, so that the communication for VMs in network 2.2.2.0/24 is transparent? http://docs.cloudstack.apache.org/projects/cloudstack-administration/en/4.8/_images/network-setup-zone.png -- Rafael Weingärtner
