My team has been working for three weeks with CloudStack architecture design and we are struggling to put together a network architecture that we feel will scale. From everything I can tell, CloudStack requires a a very large layer 2 network when using shared guest networks. We are looking to deploy almost a thousand physical hosts across 25 cabinets with over 4000 VMs in the next 18 months and having a broadcast domain this large feels problematic.
How have others solved this problem? I don't have a need or a desire for isolation and even if I had 100 guest networks I would still have to tag their VLANs into every host port. There doesn't seem to be a way to tie a network to anything smaller than a zone. One solution we are looking into is Cisco's 1000v and utilizing VXLANs. This will allow us scale down the broadcast domains. I don't think CloudStack has support in configuring their VXLAN settings? Any comments or suggestions would be appreciated. Justin
