I am using http://hyperledger-fabric-doc.readthedocs.io/en/latest/getting_started.html for Hyperledger Fabric setup in Ubuntu VM. As per tutorial (fabric-samples/first-netwo
It isn't to the point of being "dynamic" just yet. However, the reconfiguration is done using the configtxlator tool to read the genesis block and modify it's contents, then submit it as a new transaction that updates the network/channel configuration. Please see the tutorial on configtxlator here.