lighthouse/book/src/testnet-validator.md

Become a Testnet Validator

Joining an Eth2 testnet is a great way to get familiar with staking in Phase 0. All users should experiment with a testnet prior to staking mainnet ETH.

To join a testnet, you can follow the Become an Eth2 Mainnet Validator instructions but with a few differences:

1. Use the appropriate Eth2 launchpad website:
   • Pyrmont
2. Instead of --network mainnet, use the appropriate network flag:
   • --network pyrmont: Pyrmont.
3. Use a Goerli Eth1 node instead of a mainnet one:
   • For Geth, this means using geth --goerli --http.
4. Notice that Lighthouse will store its files in a different directory by default:
   • ~/.lighthouse/pyrmont: Pyrmont.

Never use real ETH to join a testnet! All of the testnets listed here use Goerli ETH which is basically worthless. This allows experimentation without real-world costs.