Layer 1 Network@Sui $SUI experienced a prolonged outage lasting nearly 6 hours, disrupting all transaction activities on the chain. This is considered the second major technical challenge since Mainnet.
- The incident started at 2:52 PM (14/01) and lasted until 8:44 PM (14/01), spanning 5 hours and 52 minutes (UTC)
1. Causes and Impact
- The cause was a "consensus failure" affecting validators, leading to a complete network halt
=> Sui Foundation did not disclose the exact cause, but it was related to validator coordination issues
=> Sui had previously experienced this issue twice: in November 2024, it was down for 2.5 hours due to a consensus error.
And in December 2025, it faced reduced consensus performance, though for a shorter duration.
- This caused over $1 billion in on-chain value to become temporarily inaccessible, with transactions halted and applications like SuiScan and Slush becoming unresponsive or offline
=> The incident raised concerns about the network's reliability for financial infrastructure, as repeated outages revealed fragility in its high-speed design architecture
2. Resolution and Recovery
- The Sui Core team announced they were investigating and deploying a fix. Validators rolled out the update, and by 8:44 PM UTC, the network had "fully resumed" operations with transactions continuing normally.
3. Blockchains That Have Never Been Offline
- Bitcoin ( $BTC ): Bitcoin has operated continuously without any outages since 2009. This is a prime example of the resilience of a decentralized network, achieving 100% uptime for over 15 years—even during global incidents like AWS outages
- Ethereum ( $ETH ): Ethereum has reached a 10-year uptime milestone without missing a single block, despite major forks and upgrades (such as The Merge). The network prioritizes consistency and has never fully halted, unlike high-speed chains such as Solana or Sui.
- Cardano ( $ADA): Cardano stands out with zero downtime for over 8 years (approximately 2,129 days as of today), never halting the network, losing funds, or rolling back. It is among the most stable PoS chains, surpassing competitors like Solana or Polygon
- Additionally, $NEAR, Tezos ( $XTZ), or Polkadot ( $DOT) have experienced brief outages at times, but have never suffered a complete network shutdown like Sui
- Similarly, Aptos ($APT), which uses the same Move language, has also faced some downtime incidents, particularly a 5-hour outage on October 18, 2023—coinciding with its 1-year mainnet anniversary
- What do you guys think?