how to add raft instead of kafka in hyperledger fabric? - hyperledger-fabric

Question

How to add raft instead of kafka in hyperledger fabric altoros fabric-supply-chain project ?
here's my configtxtemplate-OneOrg-orderer.yaml file
---
################################################################################
#
# Profile
#
# - Different configuration profiles may be encoded here to be specified
# as parameters to the configtxgen tool
#
################################################################################
Profiles:
OrdererGenesis:
Orderer:
<<: *OrdererDefaults
Organizations:
- *OrdererOrg
Consortiums:
SampleConsortium:
Organizations:
- *ORG1
common:
Consortium: SampleConsortium
Application:
<<: *ApplicationDefaults
Organizations:
- *ORG1
CHANNEL_NAME:
Consortium: SampleConsortium
Application:
Organizations:
- *ORG1
################################################################################
#
# Section: Organizations
#
# - This section defines the different organizational identities which will
# be referenced later in the configuration.
#
################################################################################
Organizations:
# SampleOrg defines an MSP using the sampleconfig. It should never be used
# in production but may be used as a template for other definitions
- &OrdererOrg
# DefaultOrg defines the organization which is used in the sampleconfig
# of the fabric.git development environment
Name: OrdererMSP
# ID to load the MSP definition as
ID: OrdererMSP
# MSPDir is the filesystem path which contains the MSP configuration
MSPDir: crypto-config/ordererOrganizations/DOMAIN/msp
- &ORG1
# DefaultOrg defines the organization which is used in the sampleconfig
# of the fabric.git development environment
Name: ORG1MSP
# ID to load the MSP definition as
ID: ORG1MSP
MSPDir: crypto-config/peerOrganizations/ORG1.DOMAIN/msp
AnchorPeers:
# AnchorPeers defines the location of peers which can be used
# for cross org gossip communication. Note, this value is only
# encoded in the genesis block in the Application section context
- Host: peer0.ORG1.DOMAIN
Port: 7051
################################################################################
#
# SECTION: Orderer
#
# - This section defines the values to encode into a config transaction or
# genesis block for orderer related parameters
#
################################################################################
Orderer: &OrdererDefaults
# Orderer Type: The orderer implementation to start
# Available types are "solo" and "kafka"
OrdererType: solo
Addresses:
- orderer.DOMAIN:7050
# Batch Timeout: The amount of time to wait before creating a batch
BatchTimeout: 2s
# Batch Size: Controls the number of messages batched into a block
BatchSize:
# Max Message Count: The maximum number of messages to permit in a batch
MaxMessageCount: 10
# Absolute Max Bytes: The absolute maximum number of bytes allowed for
# the serialized messages in a batch.
AbsoluteMaxBytes: 98 MB
# Preferred Max Bytes: The preferred maximum number of bytes allowed for
# the serialized messages in a batch. A message larger than the preferred
# max bytes will result in a batch larger than preferred max bytes.
PreferredMaxBytes: 512 KB
Kafka:
# Brokers: A list of Kafka brokers to which the orderer connects
# NOTE: Use IP:port notation
Brokers:
- 127.0.0.1:9092
# Organizations is the list of orgs which are defined as participants on
# the orderer side of the network
Organizations:
################################################################################
#
# SECTION: Application
#
# - This section defines the values to encode into a config transaction or
# genesis block for application related parameters
#
################################################################################
Application: &ApplicationDefaults
# Organizations is the list of orgs which are defined as participants on
# the application side of the network
Organizations:
Can you please check where I'm going wrong and in which files i have to make changes.
I went through the docs of raft but i couldn't understand it well and there is no good source or tutorial that i could go through. If you know any good source or example then please help.
I see the hyperledger fabric community is not as strong as bitcoin or ethereum like blockchains. I am facing lot of trouble to build an application on it. I would request you to help me from where i can learn the best.

Answer 1

You can read in documentation for more details and explanations, while key concepts are:
In order to work with Raft you need to configure your ordering service to work with TLS.
Change orderer type to be
OrdererType: etcdraft
You need to setup your concenters set (Raft replicas) by adding into configuration following section:
Consenters:
- Host: raft0.example.com
Port: 7050
ClientTLSCert: path/to/ClientTLSCert0
ServerTLSCert: path/to/ServerTLSCert0
- Host: raft1.example.com
Port: 7050
ClientTLSCert: path/to/ClientTLSCert1
ServerTLSCert: path/to/ServerTLSCert1
- Host: raft2.example.com
Port: 7050
ClientTLSCert: path/to/ClientTLSCert2
ServerTLSCert: path/to/ServerTLSCert2
where you provide configuration to setup your cluster including TLS certificates for your concenters.
For example profile for Raft might look as following, SampleDevModeEtcdRaft profile:
SampleDevModeEtcdRaft:
<<: *ChannelDefaults
Capabilities:
<<: *ChannelCapabilities
Orderer:
<<: *OrdererDefaults
OrdererType: etcdraft
EtcdRaft:
Consenters:
- Host: raft0.example.com
Port: 7050
ClientTLSCert: path/to/ClientTLSCert0
ServerTLSCert: path/to/ServerTLSCert0
- Host: raft1.example.com
Port: 7050
ClientTLSCert: path/to/ClientTLSCert1
ServerTLSCert: path/to/ServerTLSCert1
- Host: raft2.example.com
Port: 7050
ClientTLSCert: path/to/ClientTLSCert2
ServerTLSCert: path/to/ServerTLSCert2
Organizations:
- *OrdererOrg
Capabilities:
<<: *OrdererCapabilities
Application:
<<: *ApplicationDefaults
Organizations:
- <<: *OrdererOrg
Consortiums:
SampleConsortium:
Organizations:
- *Org1
- *Org2