Accessing pre-regenesis history

This tutorial explains how to access transaction history between 23 June 2021 and the final regenesis. Because of our final regenesis on 11 November 2021, older transactions are not part of the current blockchain and do not appear on Etherscan (opens in a new tab).

Dune access

You can use a query on Dune Analytics (opens in a new tab), similar to this query (opens in a new tab). You have to log on with a Dune account, but their free tier is sufficient.

Alternatively, to run custom queries in Dune, you can use the optimism_legacy_ovm1 schema defined in Dune Docs here (opens in a new tab).

Lost data directories

Three data directories that were used by legacy L2Geth Sequencer instances during the period of January 2021 to July 2021 had been errantly deleted during an infra cleanup in August 2023.

These data directories contained information about the effects of transactions, once executed. This information can only be obtained by properly executing the transaction chain. The most valuable data within these directories was (1) events emitted by smart contracts during each transaction and (2) the success state of the transaction (whether or not the transaction executed or reverted). This information is valuable for tracking things like ETH transfers or ERC-20 token transfers. Without this we can still know the final set of balances but the intermediate balances become opaque.

The transaction data for this period of time was published to a smart contract on Ethereum called the CanonicalTransactionChain (opens in a new tab). While it is theoretically possible to recover the data by downloading and re-executing this chain of transactions from Ethereum, this is a labor intensive and costly task that may not fully recover the data. The OP Labs's team did attempt data recover efforts, including reaching out to several partners.

Impact

No state, balances, or user assets were lost. Most of the impact is felt by data providers who want complete data sets for analysis purposes and by individuals who may want this information for tax purposes.

Since this was very early during the history of OP Mainnet there are relatively few transactions in this period and this data is infrequently requested. Most requests for this data came from individuals who needed access to this information for the 2021 tax season though this is mostly no longer relevant today (many people who needed this data already retrieved it).

Going forward

We recognize the inconvenience this has caused some of our community and their users and we're sorry for the frustrations. In an effort to prevent similar situations from happening again in the future, we are evaluating and updating existing processes and frameworks.