Have you seen the network/bandwidth caps that Rackspace places on their cloud servers?
From the Rackspace Cloud Server FAQ:
"Your Cloud Server has a bandwidth cap that is applied in relation to the size of the server. Please note that the bandwidth caps are placed on outbound bandwidth only. Inbound bandwidth is not capped."
Server Size Public Limit ServiceNet Limit 256MB 10 Mbps 20 Mbps 512MB 20 Mbps 40 Mbps 1024MB 30 Mbps 60 Mbps 2048MB 40 Mbps 80 Mbps 4096MB 50 Mbps 100 Mbps 8192MB 60 Mbps 120 Mbps 15872MB 70 Mbps 140 Mbps
I was going to use the Rackspace Cloud to do some performance testing of a new server. I wanted to run 2 servers in a clustered mode, replicating data to each other. My first concern was the speed of the internal network interconnects between cloud nodes.
After doing some research, I realized the bandwidth caps make it a non-starter. 20-140 Mbps private interconnects?? That's not enough. I would saturate the network almost immediately, even on their largest server class. Sorry Rackspace.