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This guide shows you how to configure your node to run as an archive node. Archive nodes store the complete history of the blockchain, including all historical states.

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Overview

Archive nodes maintain the entire state history of the blockchain, allowing you to query any historical state at any block height. This is useful for:
  • Block explorers that need to provide historical data
  • Analytics and data analysis applications
  • Services that need to query historical state
  • Debugging and auditing purposes
Archive nodes use execution-layer sync but configure the execution client to retain all historical state data instead of pruning it.

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Requirements

  • OP Mainnet: Requires the bedrock datadir
  • Other OP Stack networks: No datadir required
  • Storage: Archive nodes require significantly more disk space than regular nodes (several terabytes for OP Mainnet)
  • Sync time: Archive sync with execution-layer mode is faster than full block-by-block execution

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Configuration

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Configuration for op-node

Set the following flag on op-node: 
--syncmode=execution-layer
The --syncmode=execution-layer flag is not the default setting and must be explicitly configured.

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Configuration for op-geth

Set the following flags on op-geth: 
--syncmode=full
--gcmode=archive
Both flags are not the default settings and must be explicitly configured. The --syncmode=full flag ensures every block is executed, and --gcmode=archive disables state pruning.

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Configuration for Nethermind

Archive sync can be enabled by using the archive configuration for your network (configurations with _archive suffix): 
--config op-mainnet_archive
Replace op-mainnet_archive with the appropriate archive configuration for your network (e.g., op-sepolia_archive for OP Sepolia).

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Archive mode with alternative clients

Alternative execution clients such as reth and op-erigon are designed as archive nodes by default, which means they always maintain the complete history of the chain. When using these clients with execution-layer sync, they will automatically operate in archive mode.

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Configuration for op-node with reth

Set the following flags on op-node: 
--syncmode=execution-layer
--l2.enginekind=reth
Both flags are not the default setting and must be explicitly configured on op-node. reth operates as an archive node by default.

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Configuration for op-node with op-erigon

Set the following flags on op-node: 
--syncmode=execution-layer
--l2.enginekind=erigon
Both flags are not the default setting and must be explicitly configured on op-node. op-erigon operates as an archive node by default.

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How archive sync works

With execution-layer sync mode enabled:
  1. Initial sync: The node downloads block headers and data through the P2P network
  2. Block execution: The node executes every block in the chain to build the complete state history
  3. State retention: Unlike regular nodes, archive nodes never prune historical state data
  4. Faster than legacy: While still executing all blocks, this is faster than the legacy consensus-layer sync because block data is retrieved via P2P instead of being derived from L1

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Storage considerations

Archive nodes require substantial storage:
  • OP Mainnet: Several terabytes and growing
  • Other networks: Varies by network age and activity
  • Growth rate: Storage requirements increase continuously as new blocks are added
  • Recommendation: Use fast SSD storage for optimal performance

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Next steps