author_rotateKeys - Kusama RPC Method
Generate new session keys for validator operations on Kusama. Essential for validator setup, key rotation, and security best practices on Polkadot's canary network for real-world testing with live economic conditions.
Generate a new set of session keys on Kusama. This method creates fresh cryptographic keys for all session key types (e.g., BABE, GRANDPA, ImOnline, ParaValidator, AuthorityDiscovery) and stores them in the node's local keystore. The returned concatenated public keys must be registered on-chain via session.setKeys.
Why Kusama? Build on Polkadot's canary network for real-world testing with live economic conditions with 7-day governance cycles (vs 1 month on Polkadot), lower bonding requirements, live KSM token economy, and first-to-market feature testing.
When to Use This Method
author_rotateKeys is critical for experimental dApp developers, parachain teams, and early adopters validating new features:
- Validator Setup — Generate initial session keys when setting up a new validator on parachain experimentation, early feature deployment, and production-grade testing with real value
- Key Rotation — Periodically rotate keys for operational security best practices
- Recovery — Generate replacement keys after a potential key compromise or node migration
- Validator Upgrades — Produce new keys when moving a validator to new hardware
Code Examples
Common Use Cases
1. Complete Validator Setup Workflow
Full end-to-end validator setup on Kusama:
async function setupValidator(api, stashAccount) {
// Step 1: Generate session keys
const keys = await api.rpc.author.rotateKeys();
console.log('Generated session keys:', keys.toHex());
// Step 2: Register keys on-chain
const setKeysTx = api.tx.session.setKeys(keys, '0x');
await new Promise((resolve, reject) => {
setKeysTx.signAndSend(stashAccount, ({ status, events }) => {
if (status.isFinalized) {
const success = events.some(({ event }) =>
api.events.system.ExtrinsicSuccess.is(event)
);
if (success) {
console.log('Session keys registered successfully');
resolve();
} else {
reject(new Error('setKeys transaction failed'));
}
}
});
});
// Step 3: Verify registration
const nextKeys = await api.query.session.nextKeys(stashAccount.address);
console.log('Keys registered for next session:', nextKeys.isSome);
}2. Scheduled Key Rotation
Automate periodic key rotation for security:
async function scheduleKeyRotation(api, validatorAccount, intervalDays = 30) {
const intervalMs = intervalDays * 24 * 60 * 60 * 1000;
async function rotateAndRegister() {
try {
const newKeys = await api.rpc.author.rotateKeys();
console.log(`Rotated keys at ${new Date().toISOString()}`);
const tx = api.tx.session.setKeys(newKeys, '0x');
await tx.signAndSend(validatorAccount);
console.log('New keys registered — active next session');
} catch (error) {
console.error('Key rotation failed:', error.message);
}
}
// Initial rotation
await rotateAndRegister();
// Schedule future rotations
setInterval(rotateAndRegister, intervalMs);
}Validator Setup Workflow
- Generate keys — Call
author_rotateKeyson your validator node - Register on-chain — Submit
session.setKeys(keys, proof)extrinsic from your stash account - Wait for session — Keys become active at the start of the next session
- Verify — Query
session.nextKeysto confirm registration
Security Considerations
- Local access only — Only call this method on your own validator node via localhost
- Never expose publicly — This RPC method is marked as
unsafeand should not be accessible from the internet - Keystore security — Session keys are stored in the node's keystore directory on disk
- Rotate regularly — Follow a key rotation schedule to limit exposure from potential compromises
- Backup awareness — New keys replace old ones in the keystore; old keys cannot be recovered
Error Handling
| Error Code | Description | Solution |
|---|---|---|
| -32603 | RPC call is unsafe | Enable --rpc-methods unsafe flag on the node (local access only) |
| -32601 | Method not found | Verify the node has the author RPC module enabled |
| -32603 | Internal error | Check node keystore permissions and disk space |
Related Methods
author_hasSessionKeys— Check if session keys exist in the keystoreauthor_submitExtrinsic— Submit thesetKeystransactionauthor_pendingExtrinsics— View pending transactionssession_nextKeys— Query registered session keys on-chain
author_submitAndWatchExtrinsic
Submit an extrinsic and subscribe to lifecycle status updates on Kusama. Track transactions from pool admission through finalization with real-time WebSocket events for parachain experimentation, early feature deployment, and production-grade testing with real value.
payment_queryInfo
Estimate transaction fees on Kusama. Get the weight, dispatch class, and partial fee for an extrinsic before submitting it to the network.