VLS Containers

Installing Docker

Docker Documentation

Docker Engine is available on a variety of Linux distros, macOS, and Windows 10 through Docker Desktop, and as a static binary installation. Refer to the official docker documentation

• Ubuntu
• Fedora

Note: The compose files present within this repository make use of docker compose v2 the minimum supported version is v2.26.0.

VLS standalone Setup

Below are the steps required to run vlsd2 as a standalone container.

Docker Image

# Build the latest docker image
cd vlsd
docker build -t vlsd .

Volume Creation

docker volume create vls_data

Environment Variables

VLS container needs the follwing environment variables set:

• BITCOIND_RPC_URL: URL of bitcoind's RPC port.
• VLS_NETWORK: testnet or regtest.

Frequently used optional environment variables are:

• VLS_PERMISSIVE
• RUST_LOG

vlsd2 Command Arguments

Required command arguments:

• connect: URL of remote_hsmd_socket running in the lightning node.

For information on all possible arguments to vlsd see documentation.

Build Arguments

For building the container its required to provide following build arguments:

• VLS_REPO url for git repo to use for building binaries.
• VLS_GIT_HASH commit sha/tag/branch to use from git repo.
• TXOO_PUBLIC_KEY public key for trusted TXOO.

Running container

There is a docker-compose.yml in the vlsd folder which can be used to run a standalone vlsd service with network_mode set to host.

cd vlsd
export VLS_REPO=$VLS_REPO
export VLS_GIT_HASH=$VLS_GIT_HASH
export TXOO_PUBLIC_KEY=$TXOO_PUBLIC_KEY
docker compose up

Note: Make sure to set BITCOIND_RPC_URL and CLN_REMOTE_HSMD_URL as either environment variables or in the docker-compose.yml file before running the above command.

If you wish to run it as a standalone container without using docker compose you can use the following command:

docker run \
  -d \
  --rm \
  --name vlsd \
  --network host \
  --build_arg VLS_GIT_HASH=$VLS_GIT_HASH
  --build_arg VLS_REPO=$VLS_REPO
  --build_arg TXOO_PUBLIC_KEY=$TXOO_PUBLIC_KEY
  -e VLS_NETWORK=testnet \
  -e BITCOIND_RPC_URL=$BITCOIND_RPC_URL \
  --mount 'type=volume,src=vls_data,dst=/home/vls/.lightning-signer' \
  vlsd \
  --connect=$CLN_REMOTE_HSMD_URL

Single Node Setup

You can run bitcoind, lightningd, txood and vlsd on a single node using available docker compose file in the main directory.

Note: Use this only for experimentation and testing purposes as running vlsd on the same machine as CLN is not as secure as running it on dedicated hardware.

Volume Creation

Testnet:

docker volume create bitcoin_data
docker volume create lightning_data
docker volume create txoo_data
docker volume create vls_data

The regtest docker compose configuration doesn't use external volumes. The automatically created volumes can be destroyed via the down --volumes docker compose command.

Docker Compose Run

docker compose --profile vls up --build

Selecting Bitcoin Chains

We have two possible overrides over the default testnet configuration in docker-compose.yml:

• docker-compose.testnet.yml
• docker-compose.regtest.yml

To use override we have to pass it down both the config using -f flag:

export DOCKER_COMPOSE_OVERRIDE=docker-compose.testnet.yml
export COMPOSE_PROJECT_NAME=testnet
docker compose --profile vls -f docker-compose.yml -f $DOCKER_COMPOSE_OVERRIDE up --build

Note: Even while using testnet running using the override is recommended as that will expose the P2P port for bitcoind and P2P port for lightningd on the host.

Single Node without VLS

To run a single node without vls service we can use the same docker-compose.yml file in the main directory by just removing the profile flag vls from all commands.

docker compose -f docker-compose.yml -f $DOCKER_COMPOSE_OVERRIDE up --build

Above command will run bitcoind, lightningd and txood services on a single node.

First Time Chain Sync

It's quite possible that while syncing for the first time bitcoind would be unresponsive to rpc calls made by core-lightning, vls, etc. To remedy such scenario where other containers would fail to start we can instead start with just bitcoind and txood

docker compose --profile vls stop
docker compose -f docker-compose.yml -f docker-compose.testnet.yml up bitcoin-core txoo -d

Let the chain sync you can check its progress using bitcoin-cli or by checking status of docker container's health

docker container exec bitcoind-test bitcoin-cli getblockchaininfo
docker ps

Also, given there is a dependency of core-lightning on txoo it is a good idea to wait sometime so that all attestations are available for it to retrieve and txoo is healthy. txoo container health can be checked using docker

docker ps

After the chain sync has completed we can stop the containers and restart the whole system again

docker compose --profile vls stop
docker compose --profile vls -f docker-compose.yml -f docker-compose.testnet.yml up -d

Interacting with Containers

We can use the docker container exec <CONTAINER_NAME> <COMMAND> command to interact with containers and interact with setup using command line tools like bitcoin-cli, lightning-cli, vls-cli, etc.

Regtest Commands

Generate Address for node:

docker container exec bitcoind-regtest bitcoin-cli getnewaddress

Generate Blocks

docker container exec bitcoind-regtest bitcoin-cli generatetoaddress 50 $NODE_ADDRESS

Testnet CLN + CLBOSS Commands

# Create a connection to a random node (maybe from 1ML.com)
docker container exec lightningd-test lightning-cli --testnet connect \
  02ae1e6091d2a9c4db5096558668d2456b1c0e9067cb72273eab1199bcfb208888 67.227.190.47:9735

# Allocate an onchain address to fund the node
docker container exec lightningd-test lightning-cli --testnet newaddr

# List onchain and channel funds
docker container exec lightningd-test lightning-cli --testnet listfunds

# Show CLBOSS status
docker container exec lightningd-test lightning-cli --testnet clboss-status | less

# Show node summary status
docker container exec lightningd-test lightning-cli --testnet summary

Debugging Containers

Checking running status and health of containers

docker ps

Getting logs from container

# CONTAINER_NAME=lightningd-test
docker container logs $CONTAINER_NAME > $CONTAINER_NAME.log

Restarting containers

cd vls-container
docker compose --profile vls stop
# to start testnet
docker compose --profile vls up

Generating Backtrace from CLN core dump

# attach to the lightningd container
docker container exec -u root -it lightningd-test sh

# install gdb
apk add gdb
gdb /usr/libexec/c-lightning/plugins/pay /home/lightning/.lightning/testnet/core

# get backtrace
bt

Delete containers

cd vls-container
docker compose --profile vls down

NOTE: If you want to start fresh make sure to delete the created docker volumes as well.

Choosing Versions

The currently set default versions for services is as follows in the .env file:

• Bitcoin Core: v26.0
• Core Lightning: v24.02.2
• TXOO: v0.8.1
• VLS: v0.12.0

You just can switch to a particular version/commit for a service by updating the git hash and then rebuilding the service:

cd vls-container
# update bitcoin core version
sed -i 's/23.0/23.2/g' .env
# build images again
docker compose --profile vls build

Note: For bitcoind its also important to update the BITCOIN_SHA256SUMS_HASH. It is the SHA256 HASH of SHA256SUMS file.

Future Work

• standalone dockerfile for vlsd
• docker compose for vls
• standalone docker image for txood
• standalone docker image for lightningd
• standalone docker image for bitcoind
• supporting signet
• Profile configuration to run vls
• Healthcheck for txoo
• Healthcheck for vls
• Lightning Storage Server Dockerfile and Compose Service
• Postgres Service for Lightning Storage Server

References

• bitcoind by @ruimarinho
• lightningd with clboss by @tsjk
• elements lightning by @ElementsProject
• docker compose by @LukasBahrenberg