Ethereum based layer-2 scaling solution Arbitrum faced a brief network downtime in the evening hours of 9th January 2022. After a 7 hour downtime, it released a report explaining the network outage was due to a hardware failure in its main sequencer node. The issue was resolved, along with its Sequencer and all public RPC nodes, becoming fully operational. Furthermore, the post read:
The core issue was a hardware failure in our main Sequencer node. While we generally have redundancies that would allow a backup Sequencer to seamlessly take control, these also failed to take effect this morning due to a software upgrade in the process. As a result, the Sequencer stopped processing new transactions. We’d like to stress that Arbitrum is a Layer 2 network on Ethereum, and the network is designed to sustain even permanent Sequencer failures by falling back to using Ethereum to process transactions.
In addition to that, the blog post mentions that the team behind the project is working to implement additional redundancies to increase network stability. Going forward, the company plans to minimize Sequencer downtime to achieve the ‘ultimate goal of full decentralization’.
The scaling solution was hit by similar issues before, though today’s incident appears to be more severe. Last September, the Arbitrum chain suffered another network outage but was resolved within an hour.
Optimistic rollups like Arbitrum are prone to issues
Arbitrum One was developed by Offchain labs to leverage Optimistic Rollups, which process transactions at much higher speeds and lower costs than the base chain. Optimistic Rollups don’t handle computation by default, but they are prone to issues that it can take up to a week to send funds to mainnet as withdrawals are subject to a challenging period.
In contrast to that, Arbitrum’s total value locked [TVL] has quickly risen compared to other similar layer-2 projects.
In fact, according to analytics website l2beat, the layer 2 solution holds over $2.5 billion in TVL. Since it launched on the mainnet in August 2021, it has attracted several of Ethereum’s top DeFi protocols such as Balancer and Uniswap, Aave, MakerDAO, Chainlink with more expected to follow in the future.