Modifying the genesis block using configtxlator

Question

I'm a little confused as to how to modify the system channel configuration once the Fabric network is operational.

I gather that the configtxlator tool can be used to create a patch transaction with the necessary changes, but how is this transaction then applied to the system channel? Can the peer channel update CLI tool be used for this?

Answer 1

You can find how-to tour on reconfiguring the channel with configtxlator tool. Basically the high level flow will be:

1. Decode the configuration into json using configtxlator.
2. Extract config section
3. Create new configuration
4. Encode both new and old configs
5. Send them to compute the config update delta
6. Decode the config update and wrap up into envelope
7. Produce new config transaction
8. Update channel by submitting new config.

Here is the link for official docs describing reconfiguration flow in details.

And yes you can use peer cli tool to update the configuration as following:

peer channel update -f config_update_as_envelope.pb -c mychannel -o orderer:7050