The process to create a network is both social and technical: social because someone (that we will call Coordinator) needs to find at least three other Members willing to join the network, and coordinate the effort; technical because each member of the network needs to set up a machine running BigchainDB. (Note: a Coordinator is a Member as well.)
A BigchainDB Network (Network henceforth) is a set of 4 or more BigchainDB Nodes (Node henceforth). Every Node is independently managed by a Member, and runs an instance of the BigchainDB Server software. At the Genesis of a Network, there MUST be at least 4 Nodes ready to connect. After the Genesis, a Network can dynamically add new Nodes or remove old Nodes.
A Network will stop working if more than one third of the Nodes are down. The bigger a Network, the more failures it can handle. A Network of size 4 can tolerate only 1 failure, so if 3 out of 4 Nodes are online, everything will work as expected. Eventually, the Node that was offline will automatically sync with the others.
This tutorial assumes you have basic knowledge on how to manage a GNU/Linux machine. The commands are tailored for an up-to-date Debian-like distribution (we use an Ubuntu 17.10 Virtual Machine on Microsoft Azure): if you are on a different distribution you might need to adapt the name of the packages installed.
We don't make any assumptions on where you run the Node. You can run the BigchainDB Server on a Virtual Machine on the cloud, on a machine in your data center, on a Raspberry Pi. Just make sure that your Node is reachable by the other Nodes, a non-exhaustive list of examples:
- good: all Nodes running in the cloud using public IPs.
- bad: some Nodes running in the cloud using public IPs, some Nodes in a private network.
- good: all Nodes running in a private network.
The rule of thumb is: if Nodes can ping each other, then you are good to go.
The next sections are labelled with Member or Coordinator, depending on who should follow the instructions. Remember, a Coordinator is also a Member.
Every Member in the Network must set up its own Node. The process consists of installing three components, BigchainDB Server, Tendermint Core, and MongoDB, and configure the firewall.
Important note on security: it's up to the Member to harden their system.
BigchainDB Server requires Python 3.6+, make sure your system has it. Install the required packages:
sudo apt install -y python3-pip libssl-devNow install the latest version of BigchainDB. Check the project page on PyPI for the last version (2.0.0a5 at the time of writing) and install it:
sudo pip3 install bigchaindb==2.0.0a5Check you installed the correct version of BigchainDB Server with bigchaindb --version.
Install a recent version of MongoDB. BigchainDB Server requires 3.4 or newer.
sudo apt install mongodbThe package manager should take care of installing the startup script for MongoDB as well.
Install a recent version of Tendermint. BigchainDB Server requires 0.19 or newer.
sudo apt install unzip
wget https://github.com/tendermint/tendermint/releases/download/v0.19.3/tendermint_0.19.3_linux_amd64.zip
unzip tendermint_0.19.3_linux_amd64.zip
rm tendermint_0.19.3_linux_amd64.zip
sudo mv tendermint /usr/local/binMake sure to accept inbound connections to (22, you don't want to lock you out), 9984, 9985, and 46656.
sudo ufw allow 22/tcp
sudo ufw allow 9984/tcp
sudo ufw allow 9985/tcp
sudo ufw allow 46656/tcp
sudo ufw enableSome cloud providers, like Microsoft Azure, require you to go through their portal to allow inbound connections on custom ports.
To configure BigchainDB Server, run:
bigchaindb configureThe first question is API Server bind? (default `localhost:9984`), to expose the API to the public, bind the API Server to 0.0.0.0:9984. Unless you have specific needs, you can keep the default value for all other questions.
A Node is identified by the triplet <hostname, address, public_key>.
As a Member, it's your duty to create and store securely your private key, and share your hostname, address, and public_key with the other members of the network.
To generate all of that, run:
tendermint initThe public_key and address are stored in the file .tendermint/config/priv_validator.json, and it should look like:
{
"address": "5943A9EF6285791A504918E1D117BC7F6A615C98",
"pub_key": {
"type": "AC26791624DE60",
"value": "W3tqeMCU3d4SHDKqrwQWTahTW/wpieIAKZQxUxLv6rI="
},
"last_height": 0,
"last_round": 0,
"last_step": 0,
"priv_key": {
"type": "954568A3288910",
"value": "3sv9aExgME6MMjx0JoKVy7KtED8PBiPcyAgsYmVizslbe2p4wJTd3hIcMqqvBBZNqFNb/CmJ4gAplDFTEu/qsg=="
}
}Share with all other Members your address, pub_key.value, and the host name or IP of your Node.
Important note on security: each Member should verify the data they receive from the other Members.
At this point the Coordinator should has received the data from all the Members, and should combine them in the .tendermint/config/genesis.json file:
{
"genesis_time": "0001-01-01T00:00:00Z",
"chain_id": "test-chain-la6HSr",
"validators": [
{
"pub_key": {
"type": "AC26791624DE60",
"value": "<Member 1 public key"
},
"power": 10,
"name": "<Member 1 name>"
},
{
"pub_key": {
"type": "AC26791624DE60",
"value": "<Member 2 public key>"
},
"power": 10,
"name": "<Member 2 name>"
},
{
"...": { },
},
{
"pub_key": {
"type": "AC26791624DE60",
"value": "<Member N public key>"
},
"power": 10,
"name": "<Member N name>"
}
],
"app_hash": ""
}The new genesis.json file contains the data that describes the Network.
At this point, the Coordinator must share the new genesis.json file with all Members.
At this point the Member should have received the genesis.json file.
Important note on security: each Member should verify that the genesis.json file contains the correct public keys.
The Member must copy the genesis.json file in the local .tendermint/config directory.
The Member must edit the .tendermint/config/config.toml file and make the following changes:
...
create_empty_blocks = false
...
persistent_peers = "<Member 1 address>@<Member 1 hostname>:46656,\
<Member 2 address>@<Member 2 hostname>:46656,\
<Member N address>@<Member N hostname>:46656,"
Now the Member must start both BigchainDB and Tendermint.
TBD.