Switching / Migrating Consensus Client

The key takeaway in this process is to avoid running two validator clients simultaneously. You want to avoid being punished by a slashing penalty, which causes a loss of ether.

🛑 1 Stop old consensus and old validator.

In order to export the slashing database, the validator needs to be stopped.

Lighthouse | Prysm | Lodestar

sudo systemctl stop consensus validator

Nimbus | Teku

sudo systemctl stop consensus

💽 2 Export slashing database (Optional)

EIP-3076 implements a standard to safety migrate validator keys between consensus clients. This is the exported contents of the slashing database.

Update the export .json file location and name.

Lighthouse

sudo -u consensus /usr/local/bin/lighthouse account validator slashing-protection export <lighthouse_interchange.json>

Nimbus

sudo -u consensus /usr/local/bin/nimbus_beacon_node slashingdb export slashing-protection.json

Teku

sudo -u consensus /usr/local/bin/teku/bin/teku slashing-protection export --to=<FILE>

Prysm

sudo -u validator /usr/local/bin/validator slashing-protection export --datadir=/path/to/your/wallet --slashing-protection-export-dir=/path/to/desired/outputdir

Lodestar

sudo -u validator /usr/local/bin/lodestar/lodestar validator slashing-protection export --network mainnet --file interchange.json

🚧 3 Setup and install new validator / consensus client

Now you need to setup/install your new validator but do not start running the systemd processes. Be sure to thoroughly follow your new consensus client and validator in steps 4 and 5. You will need to build/install the client, configure port forwarding/firewalls, and new systemd unit files.

✨ Pro Tip: During the process of re-importing validator keys, wait at least 13 minutes or two epochs to prevent slashing penalties. You must avoid running two consensus clients with same validator keys at the same time.

🛑 Critical Step: Do not start any systemd processes until either you have imported the slashing database or you have waited at least 13 minutes or two epochs.

📂 4 Import slashing database (Optional)

Using your new consensus client, run the following command and update the relevant path to import your slashing database from 2 steps ago.

Lighthouse

sudo -u consensus /usr/local/bin/lighthouse account validator slashing-protection import <my_interchange.json>

Nimbus

sudo -u consensus /usr/local/bin/nimbus_beacon_node slashingdb import path/to/export_dir/slashing-protection.json

Teku

sudo -u consensus /usr/local/bin/teku/bin/teku slashing-protection import --from=<FILE>

Prysm

sudo -u validator /usr/local/bin/validator slashing-protection import --datadir=/path/to/your/wallet --slashing-protection-json-file=/path/to/desiredimportfile

Lodestar

sudo -u validator /usr/local/bin/lodestar/lodestar validator slashing-protection import --network mainnet --file interchange.json

🌠 5 Start new validator and new beacon chain

Lighthouse | Prysm | Lodestar

sudo systemctl start consensus validator

Nimbus | Teku

sudo systemctl start consensus

🔥 6 Verify functionality

Check the logs to verify the services are working properly and ensure there are no errors.

Lighthouse | Prysm | Lodestar

sudo systemctl status consensus validator

Nimbus | Teku

sudo systemctl status consensus

Finally, verify your validator's attestations are working with public block explorer such as

https://beaconcha.in/

Enter your validator's pubkey to view its status.

🧯 7 Update Monitoring with Prometheus and Grafana

Review section 6 and change your prometheus.yml. Ensure prometheus is connected to your new consensus client's metrics port. You will also want to import your new consensus client's dashboard.