Teku Zero Sync

Teku now offers a Zero Sync mode that supports validation from a backup Beacon Chain provided by AVADO. Enabling Zero Sync eliminates the need to wait for your Execution Client to sync initially and reduces downtime in case of errors or maintenance.

The Zero Sync mode is not enabled by default. You can enable it by setting the MODE parameter to zerosync in the Management Page of Teku.

1. Navigate to the Management Page of Teku. You can do this by:

   • Clicking the Manage Package button immediately upon installing Teku; or equivalently,

   • Navigating to My Dapps menu, then clicking the Manage button on the Teku Consensus Client line.

1. Locate the section called "Environment Variables".

2. Insert zerosync (all small letters) into the value of the MODE parameter.

1. Click "Update environment variables". Teku will restart.

2. You can now check Teku's status by opening the DApp. With Zero Sync enabled, you will see the status of your local the Zero Sync beacon chains side by side in the header.

When your local chain is in sync, Teku will automatically start using it. You can leave Teku in Zero Sync mode such that, in the event your local Beacon Chain falls out of sync, Teku will automatically switch to the fall back Beacon Chain for continued operations.

If you wish, you can also disable the Zero Sync mode by setting the MODE parameter to standalone in the Management Page of Teku.

Caveats

Zero Sync is a Temporary Solution

Zero Sync is intended as a temporary solution to facilitate rapid validator setup. Users must transition to running their own Execution Client in sync for optimal performance.

Note that when using the Zero Sync mode while your local node is not fully synced:

• You cannot exit a validator while your node is relying on the failover server. Your node needs to be synced before you can exit the validator.

• MEV-Boost does not work.

• If you happen to hit a block proposal, an empty block will be produced, with zero block rewards. The block rewards will be "burned" and no one, including AVADO, will benefit from it.

The idea of the Zero Sync mode is to help you keep your validators attesting during the initial sync or re-sync of your node. Block production during that time will not work - but consider the alternative of not using Zero Sync and your node was offline, you would miss the block proposal anyway and would also miss out on the attestation rewards completely. So although the current setup is not optimal, it's better than being offline.

Your attention is drawn to the Zero Sync Terms and Conditions if you decide to use the facility. You can review these by following the link in the status area.

During the time when Zero Sync mode is active (and your node is still syncing), Teku will periodically report the following error (in red) in the Logs:

Remote Validator Client detected and no default fee recipient has been configured via the validators-proposer-default-fee-recipient option! It is strongly recommended to configure it to avoid possible block production failures in case the node has not been prepared for potential proposers by the Validator Client.

The error message indicates that block production will fail, as explained above.

Switching Back to Standalone Mode

Once your Beacon Chain and Execution Clients are back in sync, Teku will switch back to your local node and work with the MEV-Boost settings you have configured.

You may also change the MODE parameter to standalone to make sure Teku uses the local node.