Which is the lightest Lightning Network node setup?

Lightning Network is a Layer 2 solution on top Bitcoin (Layer 1).

Layers

Under normal conditions we should run our own Bitcoin Full Node and point the Lightning Network Node to it. This way we make sure that we are independent of any third parties to notify us about events related to our channel(s) state.

However, many people do not want/can/care to run a Bitcoin Full Node, what they would like is a quick and simple way to test some Lightning Network applications (LApps).

For the cases when the Lightning Network node has just one or two channels with little funds on them (~10 USD), then we can just connect to some third party Neutrino nodes instead of using our own full node.

DO NOT FOLLOW THIS APPROACH IF YOU HAVE MANY CHANNELS AND/OR SIGNIFICANT FUNDS!

Start the Lightning Network Node

Steps:

• Install docker and docker-compose(there are plenty of online resource on how to do this for every major OS)
• Save the below file and name it docker-compose.yaml

docker-compose.yaml

• Open a command line and go to the folder where the docker-compose.yaml was downloaded
• Run docker-compose up -d to start your Lightning Network Node
• To see the logs run docker-compose logs -f

We have to wait for a few minutes (~5–10) until the Lightning Network Node synchronizes.
A volumes folder will be created next to the the docker-compose.yaml file. The TLS Certificate and the macaroon files will be located under this folder.

Lightning Network Client

Depending on the LApp that we are testing, we might need to run some command line instructions (create wallet, open channel, etc). We will run the commands using docker exec.

Steps:

• Get the Container ID by running docker ps. Choose the Container ID corresponding to the lnd-prod name.

CONTAINER ID   IMAGE                                  NAMES
83fbf550a52b   lightninglabs/lnd:v0.12.0-beta.rc6     lnd-prod

• Use docker to execute lncli commands. For example:
  docker exec -t 83fbf550a52b /bin/lncli create
Of course, replace 83fbf550a52b with your own Container ID
• Check the Lightning Network Node state by running:
  docker exec -t 83fbf550a52b /bin/lncli getinfo

{
    "version": "0.12.0-beta.rc6 commit=v0.12.0-beta.rc6",
    ...
    "synced_to_chain": true,
    "synced_to_graph": true,
    "testnet": false,
    "chains": [
        {
            "chain": "bitcoin",
            "network": "mainnet"
        }
    ],
    ...
}

Both synced_to_chain and synced_to_graph must be true in order to consider the Node ready to use.

Neutrino

More details about Neutrino can be found here:
https://github.com/lightninglabs/neutrino