--- title: Starting a Validator --- ## Configure Solana CLI The solana cli includes `get` and `set` configuration commands to automatically set the `--url` argument for cli commands. For example: ```bash solana config set --url http://devnet.solana.com ``` While this section demonstrates how to connect to the Devnet cluster, the steps are similar for the other [Solana Clusters](../clusters.md). ## Confirm The Cluster Is Reachable Before attaching a validator node, sanity check that the cluster is accessible to your machine by fetching the transaction count: ```bash solana transaction-count ``` View the [metrics dashboard](https://metrics.solana.com:3000/d/monitor/cluster-telemetry) for more detail on cluster activity. ## Confirm your Installation Try running following command to join the gossip network and view all the other nodes in the cluster: ```bash solana-gossip spy --entrypoint devnet.solana.com:8001 # Press ^C to exit ``` ## Enabling CUDA If your machine has a GPU with CUDA installed \(Linux-only currently\), include the `--cuda` argument to `solana-validator`. When your validator is started look for the following log message to indicate that CUDA is enabled: `"[ solana::validator] CUDA is enabled"` ## System Tuning For Linux validators, the solana repo includes a daemon to adjust system settings to optimize performance (namely by increasing the OS UDP buffer limits, and scheduling PoH with realtime policy). The daemon (`solana-sys-tuner`) is included in the solana binary release. To run it: ```bash sudo solana-sys-tuner --user $(whoami) > sys-tuner.log 2>&1 & ``` ## Generate identity Create an identity keypair for your validator by running: ```bash solana-keygen new -o ~/validator-keypair.json ``` The identity public key can now be viewed by running: ```bash solana-keygen pubkey ~/validator-keypair.json ``` > Note: The "validator-keypair.json” file is also your \(ed25519\) private key. ### Paper Wallet identity You can create a paper wallet for your identity file instead of writing the keypair file to disk with: ```bash solana-keygen new --no-outfile ``` The corresponding identity public key can now be viewed by running: ```bash solana-keygen pubkey ASK ``` and then entering your seed phrase. See [Paper Wallet Usage](../paper-wallet/paper-wallet-usage.md) for more info. --- ### Vanity Keypair You can generate a custom vanity keypair using solana-keygen. For instance: ```bash solana-keygen grind --starts-with e1v1s ``` Depending on the string requested, it may take days to find a match... --- Your validator identity keypair uniquely identifies your validator within the network. **It is crucial to back-up this information.** If you don’t back up this information, you WILL NOT BE ABLE TO RECOVER YOUR VALIDATOR if you lose access to it. If this happens, YOU WILL LOSE YOUR ALLOCATION OF SOL TOO. To back-up your validator identify keypair, **back-up your "validator-keypair.json” file or your seed phrase to a secure location.** ## More Solana CLI Configuration Now that you have a keypair, set the solana configuration to use your validator keypair for all following commands: ```bash solana config set --keypair ~/validator-keypair.json ``` You should see the following output: ```text Wallet Config Updated: /home/solana/.config/solana/wallet/config.yml * url: http://devnet.solana.com * keypair: /home/solana/validator-keypair.json ``` ## Airdrop & Check Validator Balance Airdrop yourself some SOL to get started: ```bash solana airdrop 10 ``` Note that airdrops are only available on Devnet. Testnet SOL can be obtained by participating in the [Tour de SOL](../tour-de-sol/README.md) program. To view your current balance: ```text solana balance ``` Or to see in finer detail: ```text solana balance --lamports ``` Read more about the [difference between SOL and lamports here](../introduction.md#what-are-sols). ## Create Vote Account If you haven’t already done so, create a vote-account keypair and create the vote account on the network. If you have completed this step, you should see the “vote-account-keypair.json” in your Solana runtime directory: ```bash solana-keygen new -o ~/vote-account-keypair.json ``` Create your vote account on the blockchain: ```bash solana create-vote-account ~/vote-account-keypair.json ~/validator-keypair.json ``` ## Trusted validators If you know and trust other validator nodes, you can specify this on the command line with the `--trusted-validator ` argument to `solana-validator`. You can specify multiple ones by repeating the argument `--trusted-validator --trusted-validator `. This has two effects, one is when the validator is booting with `--no-untrusted-rpc`, it will only ask that set of trusted nodes for downloading genesis and snapshot data. Another is that in combination with the `--halt-on-trusted-validator-hash-mismatch` option, it will monitor the merkle root hash of the entire accounts state of other trusted nodes on gossip and if the hashes produce any mismatch, the validator will halt the node to prevent the validator from voting or processing potentially incorrect state values. At the moment, the slot that the validator publishes the hash on is tied to the snapshot interval. For the feature to be effective, all validators in the trusted set should be set to the same snapshot interval value or multiples of the same. It is highly recommended you use these options to prevent malicious snapshot state download or account state divergence. ## Connect Your Validator Connect to the cluster by running: ```bash solana-validator \ --identity ~/validator-keypair.json \ --vote-account ~/vote-account-keypair.json \ --ledger ~/validator-ledger \ --rpc-port 8899 \ --entrypoint devnet.solana.com:8001 \ --limit-ledger-size --log ~/solana-validator.log ``` Lastly, to configure log rotation, please run the following: ```bash # Setup log rotation cat > logrotate.sol < Note: You can use a > [paper wallet seed phrase](../paper-wallet/paper-wallet-usage.md) > for your `--identity` and/or > `--vote-account` keypairs. To use these, pass the respective argument as > `solana-validator --identity ASK ... --vote-account ASK ...` and you will be > prompted to enter your seed phrases and optional passphrase. Confirm your validator connected to the network by opening a new terminal and running: ```bash solana-gossip spy --entrypoint devnet.solana.com:8001 ``` If your validator is connected, its public key and IP address will appear in the list. ### Controlling local network port allocation By default the validator will dynamically select available network ports in the 8000-10000 range, and may be overridden with `--dynamic-port-range`. For example, `solana-validator --dynamic-port-range 11000-11010 ...` will restrict the validator to ports 11000-11010. ### Limiting ledger size to conserve disk space The `--limit-ledger-size` argument will instruct the validator to only retain the last couple hours of ledger. To retain the full ledger, simply remove that arg.