The steps mentioned below serve as an extention to the BYFN tutorial mentioned in hyperledger fabric and demonstrate how to add a new organisation to an existing channel.

Generate Network Artifacts

./byfn.sh -m generate

Start the network

./byfn.sh -m up 

Change to org3-artifacts directory and Generate crypto material for Org 3

../../bin/cryptogen generate --config=./org3-crypto.yaml

Print org3 using configtxgen and save the output file as org3.json in scripts directory so that it can be accessed through the cli container

../../bin/configtxgen -printOrg Org3MSP > ../scripts/org3.json

Run from first-network dir - Copy crypto-config dir to the current working directory to get the orderer ca certs which are needed for making an invoke

cp -r crypto-config/ordererOrganizations org3-artifacts/crypto-config/

Spin up the cli container

docker exec -it cli bash

Install vim & jq

apt update && apt install -y vim jq

Start configtxlator and set below variables in the cli container

configtxlator start &
CONFIGTXLATOR_URL=http://127.0.0.1:7059
ORDERER_CA=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem
CHANNEL_NAME=mychannel

Fetch the latest config block and write that to config_block.pb

peer channel fetch config config_block.pb -o orderer.example.com:7050 -c $CHANNEL_NAME --tls --cafile $ORDERER_CA

Decode the block to human readable json format and strip away header and meta data information

configtxlator proto_decode --input config_block.pb --type common.Block | jq .data.data[0].payload.data.config > config.json

Append and add org3.json and then write the output to updated_config.json

jq -s '.[0] * {"channel_group":{"groups":{"Application":{"groups": {"Org3MSP":.[1]}}}}}' config.json ./channel-artifacts/org3.json > updated_config.json

Translating original config to proto

configtxlator proto_encode --input config.json --type common.Config --output config.pb

Translating updated config to proto

configtxlator proto_encode --input updated_config.json --type common.Config --output updated_config.pb

Computing config update

configtxlator compute_update --channel_id $CHANNEL_NAME --original config.pb --updated updated_config.pb --output config_update.pb

Decoding config update

configtxlator proto_decode --input config_update.pb --type common.ConfigUpdate | jq . > config_update.json

Generating config update and wrapping it in an envelope

echo '{"payload":{"header":{"channel_header":{"channel_id":"'$CHANNEL_NAME'", "type":2}},"data":{"config_update":'$(cat config_update.json)'}}}' | jq . > config_update_in_envelope.json

Encoding config update envelope

configtxlator proto_encode --input config_update_in_envelope.json --type common.Envelope --output config_update_in_envelope.pb

Sign with org1

peer channel signconfigtx -f config_update_in_envelope.pb

To switch to Org1 set the below env variables - No need to do the below step at this point

export CORE_PEER_LOCALMSPID="Org1MSP"
export CORE_PEER_TLS_ROOTCERT_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/peers/peer0.org1.example.com/tls/ca.crt
export CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/Admin@org1.example.com/msp
export CORE_PEER_ADDRESS=peer0.org1.example.com:7051

Switch to org2 -- so that org2 will sign the pb before updating the channel

export CORE_PEER_LOCALMSPID="Org2MSP"
export CORE_PEER_TLS_ROOTCERT_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/peers/peer0.org2.example.com/tls/ca.crt
export CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org2.example.com/users/Admin@org2.example.com/msp
export CORE_PEER_ADDRESS=peer0.org2.example.com:7051

Sending config update to orderer

peer channel update -f config_update_in_envelope.pb -c $CHANNEL_NAME -o orderer.example.com:7050 --tls true --cafile $ORDERER_CA

Spin up the docker compose file for Org3 in a separate terminal

docker-compose -f docker-compose-org3.yaml up

Spin up the cli container for Org3 (Org3cli)

docker exec -it Org3cli bash

Switch to peer0 of Org3

export CORE_PEER_LOCALMSPID="Org3MSP"
export CORE_PEER_TLS_ROOTCERT_FILE=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org3.example.com/peers/peer0.org3.example.com/tls/ca.crt
export CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org3.example.com/users/Admin@org3.example.com/msp
export CORE_PEER_ADDRESS=peer0.org3.example.com:7051

Fetch the genesis block to join the peers of Org3 to the existing channel

peer channel fetch 0 mychannel.block -o orderer.example.com:7050 -c $CHANNEL_NAME --tls --cafile $ORDERER_CA

Join peer0 of Org3

peer channel join -b mychannel.block

Install chaincode on peer0 of Org3

peer chaincode install -n mycc -v 2.0 -p github.com/chaincode/chaincode_example02/go/

Switch to Peer1 of Org3, join it to the channel and install same version of chaincode on it to keep the gossip logs normal

The same version of chaincode should be installed on Org1 and Org2

switch to org 1 and install cc

peer chaincode install -n mycc -v 2.0 -p github.com/chaincode/chaincode_example02/go/

Switch to org 2 and install cc

peer chaincode install -n mycc -v 2.0 -p github.com/chaincode/chaincode_example02/go/

Chaincode upgrade should be done using the same version as install

peer chaincode upgrade -o orderer.example.com:7050 --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA -C $CHANNEL_NAME -n mycc -v 2.0 -c '{"Args":["init","a","90","b","210"]}' -P "OR ('Org1MSP.member','Org2MSP.member','Org3MSP.member')"

An invoke/ query should work to verify if the new org is successfully added to the channel

peer chaincode invoke -o orderer.example.com:7050  --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA -C $CHANNEL_NAME -n mycc -c '{"Args":["invoke","a","b","10"]}'
peer chaincode query -C $CHANNEL_NAME -n mycc -c '{"Args":["query","a"]}'

Org3 is now successfully added to the existing channel !!..