Ethereum Layer 2 Arbitrum One Hit By Another Outage

Arbitrum suffered from similar issues back in September—but they didn’t take several hours to resolve. 

Arbitrum One Goes Down 

Arbitrum One, Ethereum’s leading Layer 2 scaling solution, is down. 

The team behind the project posted a tweet Sunday afternoon confirming that the network was suffering from problems. “We are currently experiencing Sequencer downtime,” the post read. “Thank you for your patience as we work to restore it. All funds in the system are safe, and we will post updates here.” 

We are currently experiencing Sequencer downtime. Thank you for your patience as we work to restore it. All funds in the system are safe, and we will post updates here.

— Arbitrum (@arbitrum) January 9, 2022

Data from Arbiscan and Offchain Labs suggests that the last block on the project’s Arbitrum One chain was 4509808, which was processed at 10:29:22 UTC. That means it’s been down for over four hours at press time. 

Arbitrum has suffered similar issues before, though today’s incident appears to be more severe. In September, the Arbitrum One chain suffered another outage, but the problem was resolved within an hour. 

Arbitrum is Ethereum’s most used Layer 2 solution today, holding over $2.5 billion in total value locked. Since launching on mainnet in August 2021, it’s attracted several of Ethereum’s top DeFi protocols such as Balancer and Uniswap, with more expected to follow in the future. 

Arbitrum leverages Optimistic Rollups, which process transactions at significantly higher speeds and lower costs than the base chain by sending transactions as calldata to Ethereum mainnet. Optimistic Rollups don’t handle computation by default, but they suffer a weakness in that it can take up to a week to send funds to mainnet as withdrawals are subject to a challenge period. 

Optimistic Rollups are considered one of Ethereum’s two primary Layer 2 scaling weapons alongside ZK-Rollups, which use Zero-Knowledge proofs rather than the fraud proofs used in Optimistic Rollups. Ethereum believers are hoping that the emergence of new Optimistic Rollup and ZK-Rollup will help the network scale in 2022 as the completion of Ethereum 2.0, when 64 new shard chains will be added, is still some way off. 

Although Ethereum has seen increased usage over the last year thanks to growing interest in NFTs, DeFi, and crypto assets at large, it was plagued by high gas fees throughout the year as the price of ETH soared. As a result, newer Layer 1 networks like Solana and Avalanche took center stage in the latter half of 2021. 

2022 is expected to be a major year for Layer 2 adoption. However, as today’s outage proves, the Layer 2 ecosystem is still very much in its infancy—presenting an opportunity for Ethereum competitors to catch up and take some of the network’s market share. 

17:44 UTC update: Arbitrum One is still down with no further blocks processed.

This story is developing and will be updated as further details emerge. 

Arbitrum did not immediately respond to Crypto Briefing’s request for comment. 

Disclosure: At the time of writing, the author of this feature owned ETH and several other cryptocurrencies. They also had exposure to BAL and UNI in a cryptocurrency index.