How does Geth sync?

Syncing is the process by which Geth catches up to the latest Ethereum block and current global state. There are several ways to sync a Geth node that differ in their speed, storage requirements and trust assumptions. Now that Ethereum uses proof-of-stake based consensus, a consensus client is required for Geth to sync.

How do I sync a blockchain with Geth?

Running the above command starts Geth. Geth will not sync the blockchain correctly unless there is also a consensus client that can pass Geth a valid head to sync up to. In a separate terminal, start a consensus client. Once the consensus client gets in sync, Geth will start to sync too.

Does Geth support snap syncing?

Snap syncing was introduced by version 1.10.0 and was adopted as the default mode in version 1.10.4. Before that, the default was the "fast" syncing mode, which was dropped in version 1.10.14. Even though support for fast sync was dropped, Geth still serves the relevant eth requests to other client implementations still relying on it.

How does Ethereum syncing work?

Q. How do Ethereum syncing work? A. The current default mode of sync for Geth is called fast sync. Instead of starting from the genesis block and reprocessing all the transactions that ever occurred (which could take weeks), fast sync downloads the blocks, and only verifies the associated proof-of-works.