Bootstrap node

⚠️ The Forest bootstrap node connectivity turned out to be below expectations, as were the hardware requirements. As such, it's better to hold off hosting Forest as a bootstrap node until issue #4346 is resolved.

Introduction

A bootstrap node is the first node a new node contacts when it joins the network. It is responsible for providing the new node with a list of other nodes in the network, which the new node can then contact to join the network. Every Forest node has a list of bootstrap nodes that it can contact to join the network. This list is hardcoded into the node but can be modified by the user via the configuration file.

Forest as a bootstrap node

Every Forest node can act as a bootstrap node. That said, running a stateless node as a bootstrap node is recommended to lower the hardware requirements. A stateless node does not store the network's state or participate in the consensus process. It only serves as a gateway for new nodes to join the network.

Stateless node characteristics:

  • it connects to the P2P swarm but does not store the state of the network,
  • it does not sync the chain,
  • it does not validate the chain,
  • Hello requests' heaviest tipset is the genesis tipset (unless the node was initialized with a snapshot),
  • ChainExchange responses are PartialResponses.

Running a Forest node as a bootstrap node

To run Forest with the stateless mode enabled, you must set the --stateless flag when starting the node. For example:

# Mainnet
forest --stateless

# Calibnet
forest --stateless --chain calibnet

The default peer count is likely too small for a bootstrap node. You can set the --target-peer-count <number> flag to increase the number of peers. For example:

forest --stateless --target-peer-count 10000

Hardware requirements

The stateless node has lower hardware requirements than a full node. The exact requirements depend on the number of allowed peers. For 10'000 peers, 512 MiB of RAM and 1 vCPU should be sufficient.

Converting Lotus node into Forest node (and back)

You can use the forest-tool shed commands to convert a Lotus node into a Forest node without losing the peer identity.

First, the data of both the Lotus and Forest nodes must be backed up. By default, relevant keys in Lotus are in ~/.lotus/keystore and in Forest in ~/.local/share/forest/libp2p/.

Lotus to Forest

You need to convert the Lotus key into a Forest key. In the ~/.lotus/keystore directory, identify the file with the libp2p-host type. For example:

{ "Type": "libp2p-host", "PrivateKey": "<KEY>" }

Write the PrivateKey value to a file, for example lotus_key. Then, run the following command:

forest-tool shed key-pair-from-private-key $(cat lotus_key) | base64 -d > keypair

Now you can move the keypair file to the ~/.local/share/forest/libp2p/ directory. Done!

Forest to Lotus

First, convert the keypair file used by Forest into a private key used by Lotus:

❯ forest-tool shed private-key-from-key-pair > lotus_key

Then, copy the content to the relevant file's (one with the type libp2p-host in ~/.lotus/keystore/) PrivateKey value. Done!

Additional resources