Mithril Snapshot Import

Syncing a Cardano node from genesis can take a very long time. Torsten supports importing Mithril-certified snapshots of the immutable database to drastically reduce initial sync time.

How It Works

Mithril is a stake-based threshold multi-signature scheme that produces certified snapshots of the Cardano immutable database. These snapshots are verified by Mithril signers (stake pool operators) and made available through Mithril aggregator endpoints.

The import process:

Queries the Mithril aggregator for the latest available snapshot
Downloads the snapshot archive (compressed with zstandard)
Extracts the cardano-node chunk files
Parses each block using the pallas CBOR decoder
Bulk-imports blocks into Torsten's RocksDB-based ImmutableDB

Usage

torsten-node mithril-import \
  --network-magic <magic> \
  --database-path <path>

Arguments

Argument	Default	Description
`--network-magic`	`764824073`	Network magic (764824073=mainnet, 2=preview, 1=preprod)
`--database-path`	`db`	Path to the database directory
`--temp-dir`	system temp	Temporary directory for download and extraction

Examples

Mainnet:

torsten-node mithril-import \
  --network-magic 764824073 \
  --database-path ./db-mainnet

Preview testnet:

torsten-node mithril-import \
  --network-magic 2 \
  --database-path ./db-preview

Preprod testnet:

torsten-node mithril-import \
  --network-magic 1 \
  --database-path ./db-preprod

Mithril Aggregator Endpoints

Torsten automatically selects the correct aggregator for each network:

Network	Aggregator URL
Mainnet	`https://aggregator.release-mainnet.api.mithril.network/aggregator`
Preview	`https://aggregator.pre-release-preview.api.mithril.network/aggregator`
Preprod	`https://aggregator.release-preprod.api.mithril.network/aggregator`

Resume Support

The import process supports resuming interrupted downloads and imports:

If the snapshot archive has already been downloaded (same size), the download is skipped
If the archive has already been extracted, extraction is skipped
Blocks already present in the database are skipped during import

This means you can safely interrupt the import and restart it later.

After Import

Once the import completes, start the node normally. It will detect the imported blocks and resume syncing from where the snapshot left off:

torsten-node run \
  --config config.json \
  --topology topology.json \
  --database-path ./db-mainnet \
  --socket-path ./node.sock \
  --host-addr 0.0.0.0 \
  --port 3001

Disk Space Requirements

Mithril snapshots are large. Approximate sizes (which grow over time):

Network	Compressed Archive	Extracted	Final DB
Mainnet	~60-90 GB	~120-180 GB	~90-140 GB
Preview	~5-10 GB	~10-20 GB	~8-15 GB
Preprod	~15-25 GB	~30-50 GB	~20-35 GB

The temporary directory needs enough space for both the compressed archive and the extracted files. After import, temporary files are automatically cleaned up.

Note: Ensure you have sufficient disk space before starting the import. The --temp-dir flag can be used to direct temporary files to a different volume if needed.

Torsten Documentation