# Unichain Node Snapshots (/docs/unichain/technical-information/node-snapshots)

Use snapshots to quickly bootstrap Unichain nodes without a full blockchain sync.

Starting a new Unichain node from scratch requires a full blockchain sync, which can take 4 to 8 hours for mainnet and 2 to 4 hours for testnet. A snapshot can reduce this initial sync time to a few minutes.

## Snapshot Sources
Allnodes provides regularly updated snapshots for both Unichain networks. Hourly differential updates are also available for nodes that need to catch up quickly without downloading a full snapshot.

| Network         | Base image                                                                                                                                                       | 24h snapshot                                                                           | Hourly diff                                                                                                        |
| :-------------- | :--------------------------------------------------------------------------------------------------------------------------------------------------------------- | :------------------------------------------------------------------------------------- | :----------------------------------------------------------------------------------------------------------------- |
| Mainnet         | [https://snapshots.publicnode.com/unichain-geth-base.tar.lz4](https://snapshots.publicnode.com/unichain-geth-base.tar.lz4)                                       | [https://publicnode.com/snapshots#unichain](https://publicnode.com/snapshots#unichain) | [https://sdca9.share.hsforms.com/2Nxi8y1IhRPO8mluwjYKgWA](https://sdca9.share.hsforms.com/2Nxi8y1IhRPO8mluwjYKgWA) |
| Sepolia Testnet | [https://snapshots.publicnode.com/unichain-sepolia-geth-base-0-13772176.tar.lz4](https://snapshots.publicnode.com/unichain-sepolia-geth-base-0-13772176.tar.lz4) | [https://publicnode.com/snapshots#unichain](https://publicnode.com/snapshots#unichain) | [https://sdca9.share.hsforms.com/2Nxi8y1IhRPO8mluwjYKgWA](https://sdca9.share.hsforms.com/2Nxi8y1IhRPO8mluwjYKgWA) |

## Snapshot Restoration Process
These instructions assume you're working in the cloned `unichain-node` directory that contains `docker-compose.yml`. If you do not have a node running yet, follow [Set Up a Node](/docs/unichain/getting-started/set-up-a-node).

## 1. Prepare the data directory
Create the data directory that will store your blockchain data:

```bash
mkdir ./geth-data
```

For existing installations, if you have previously run the node, stop it first and clear the existing data:

```bash
docker compose down
rm -rf ./geth-data/*
```

## 2. Download the snapshot
Visit the appropriate Allnodes link from the table above and download the snapshot for your target network.

**Important**: Ensure sufficient disk space is available. The compressed snapshot archive will expand to a significantly larger size when extracted.

## 3. Extract the archive
Extract the downloaded snapshot file:

```bash
tar -I lz4 -xvf <downloaded-snapshot-filename.tar.lz4>
```

## 4. Organize the data
The extraction process creates a directory structure (typically named geth). Move the contents to your prepared data directory:

```bash
mv ./geth/* ./geth-data/
rm -rf ./geth
```

**Expected result**: The `./geth-data/` directory should contain blockchain data folders (`chaindata`, `nodes`, and others) directly, without additional nesting.

## 5. Start the node
Launch your Unichain node with the restored data:

```bash
docker compose up --build -d
```

## 6. Verify operation
Monitor the node startup and sync process:

```bash
docker compose logs -f op-geth
```

The node should begin syncing from the snapshot's block height rather than genesis. Once operation is confirmed, the downloaded snapshot archive can be deleted to recover disk space.

## Incremental Updates with Hourly Diffs
For nodes that are already synchronized but have fallen behind, hourly differential files provide a more efficient update method than full snapshots. These smaller files contain only recent blockchain changes and can quickly bring a node current without the overhead of a complete snapshot download.

Download the appropriate hourly diff from the links above and apply it to your existing node data for faster synchronization.