How the Arbitrum second-tier network bundles transactions into batches and sends them in one transfer to Ethereum. This allows you to reduce the load on the main blockchain and reduce commissions.
The sequencer is responsible for the formation and sending of packages, in the code for the on-chain publication of assemblies of which an error was found.
“Impact: Brief pause to finalize transactions on the network, otherwise the service was unaffected,” the team explained.
A failed batch transaction caused the funding mechanism to become out of sync. It consists of two wallets: a sequencer and a "gas refund". The first, by definition, has a minimum balance and is programmatically replenished with the second.
Because the transaction was not completed, the sequencer wallet did not receive a refund of the ~5 ETH spent and could not send the next packet.
After fixing the error, the mechanism works normally.
“Summarizing, we can summarize that there was a bug in the packet handler, due to which it did not publish them on the network for a while. We will soon publish a detailed analysis, and we are pleased that the fault-tolerant system worked properly during the incident, ”the developers noted.