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Joining a Running Network

Each Casper network is permissionless, enabling new validators to join the network and provide additional security to the system. This page outlines the sequence of recommended steps to spin up a validating node and join an existing network.

Step 1: Provisioning Hardware

Visit the Hardware Specifications section and provision your node hardware.

Step 2: Setting Up the Node

Follow the instructions on the Node Setup page.

Step 3: Building the Required Contracts

Use the commands below to build all the necessary contracts for bonding, retrieving rewards, and unbonding.

  1. Clone the casper-node repository.
git clone
  1. Install these prerequisites, which are also listed here.
  • Rust
  • CMake
  • pkg-config - On Ubuntu, use sudo apt-get install pkg-config
  • openssl - On Ubuntu, use sudo apt-get install openssl
  • libssl-dev - On Ubuntu, use sudo apt-get install libssl-dev
  1. Install the Rust casper-client and fund the keys you will use for bonding.

  2. Use the following commands to build the contracts in release mode. Make sure you have installed Rust.

cd casper-node
make setup-rs
make build-client-contracts

These commands will build all the necessary Wasm contracts for operating as a validator:

  • activate_bid.wasm - Reactivates an ejected validator
  • add_bid.wasm - Enables bonding for validator stake
  • delegate.wasm - Delegates stake
  • undelegate.wasm - Undelegates stake
  • withdraw_bid.wasm - Enables unbonding for validator stake

Step 4: Creating and Fund Keys for Bonding

See the Node Setup instructions if you have not generated and funded your validator keys.

Step 5: Updating the Trusted Hash

The node's config.toml needs to be updated with a recent trusted hash.

See the Trusted Hash for Synchronizing instructions if you have not set up a trusted hash during node installation.

Step 6: Starting the Node

Start the node with the casper-node-launcher:

sudo systemctl start casper-node-launcher

The above Debian package installs a casper-node service for systemd.

For more information, visit GitHub.

Step 7: Confirming the Node is Synchronized

While the node is synchronizing, the /status endpoint is available. You will be able to compare this to another node's status endpoint era_id and height to determine if you are caught up. You will not be able to perform any casper-client calls to your 7777 RPC port until your node is fully caught up.

Towards the end of the following output, notice the era_id and height that you can use to determine if your node has completed synchronizing.

Sample output of the /status endpoint
"api_version": "1.4.3",
"chainspec_name": "casper-test",
"starting_state_root_hash": "e2218b6bdb8137a178f242e9de24ef5db06af7925e8e4c65fa82d41df38f4576",
"peers": [
"node_id": "tls:0097..b253",
"address": ""
"node_id": "tls:ff95..c014",
"address": ""
"last_added_block_info": {
"hash": "8280de05cb34071f276fbe7c69a07cb325ddd373f685877911238b614bdcc5b1",
"timestamp": "2022-01-04T15:33:08.224Z",
"era_id": 3240,
"height": 430162,
"state_root_hash": "ec4ff5c4d0a9021984b56e2b6de4a57188101c24e09b765c3fee740353690076",
"creator": "01ace6578907bfe6eba3a618e863bbe7274284c88e405e2857be80dd094726a223"
"our_public_signing_key": "01cb41ee07d1827e243588711d45040fe46402bf3901fb550abfd08d1341700270",
"round_length": null,
"next_upgrade": null,
"build_version": "1.4.3-a44bed1fd-casper-mainnet",
"uptime": "25days 1h 48m 22s 47ms"

Step 8: Sending the Bonding Request

You can submit a bonding request to change your synchronized node to a validating node.

The bonding request must be sent after the node has synchronized the protocol state and linear blockchain to avoid being ejected for liveness failures.