Updating the Channel Configs in Hyperledger Fabric

Find the details under the "Adding an Org to Channel" section of tutorials. 
This is very important as you need to switch to orderer MSP to send a channel update Optional
Reference: https://hyperledger-fabric.readthedocs.io/en/release-1.4/channel_update_tutorial.html

Static Leader Election in Hyperledger Fabric Peer

How to enable static leader election in HLF?

Static leader election allows you to manually define one or more peers within an organization as leader peers. Please note, however, that having too many peers connect to the ordering service may result in inefficient use of bandwidth. To enable static leader election mode, configure the following parameters within the section of core.yaml:  

 vi /fabric-samples/config/core.yaml

peer:

    # Gossip related configuration

    gossip:

        useLeaderElection: false

        orgLeader: true

Alternatively, these parameters could be configured and overridden with environmental variables:

export CORE_PEER_GOSSIP_USELEADERELECTION=false

export CORE_PEER_GOSSIP_ORGLEADER=true

Note:

The following configuration will keep peer in stand-by mode, i.e. peer will not try to become a leader:

export CORE_PEER_GOSSIP_USELEADERELECTION=false

export CORE_PEER_GOSSIP_ORGLEADER=false

• Setting CORE_PEER_GOSSIP_USELEADERELECTION and CORE_PEER_GOSSIP_ORGLEADER with true value is ambiguous and will lead to an error.
• In static configuration organization admin is responsible to provide high availability of the leader node in case for failure or crashes.

Reference:

https://hyperledger-fabric.readthedocs.io/en/release-1.4/gossip.html?highlight=static%20leader#leader-election

Chaincode operations on Hyperledger Fabric

Objective:

• Install chaincode on peers
• Instantiate chaincode on the channel
• Upgrade chaincode
• Query chaincode
• Invoke chaincode
• List chaincodes installed and instantiated 

Reference:
https://hyperledger-fabric.readthedocs.io/en/release-1.4/build_network.html
https://hyperledger-fabric.readthedocs.io/en/release-1.4/endorsement-policies.html