One Hosting Provider's Routing Error Took 29% of Solana's Stake Offline

A newly detailed account of a routing failure at hosting provider Teraswitch shows how close Solana came to losing block finality. Roughly 29 percent of staked SOL went offline, within about 4.5 percentage points of the 33.34 percent at which the network stops finalizing blocks. CryptoSlate reported that the failure stayed below the halt threshold while independent telemetry showed delayed finality and sharply lower throughput.

The cause was a network-routing mistake, not a consensus bug and not an attack. According to an analysis by the staking protocol Marinade, Teraswitch advertised a default route from its Miami site without the attributes that describe it. A route reflector in Amsterdam then propagated that route across sites in Europe and Asia, and edge routers preferred it over the valid one. Teraswitch's own core then rejected the route as invalid, leaving twelve sites with no usable path. About 90 validators and more than 133 million SOL dropped out at once. Engineers found the software bug in roughly ten minutes, and full recovery took about 33 minutes.

The concentration number is the part that should concern stakers. Marinade's review found that a single provider hosts 27.34 percent of all staked SOL, above the Solana Foundation's 25 percent guideline, and that 94 percent of the stake on that provider went offline at the same time. Validator rewards lost during the episode were small, around 333 SOL, but the risk being measured is not lost rewards. It is whether a chain that reports thousands of validators actually has a few dozen correlated failure points.

Solana holds $5.73 billion in decentralized finance (DeFi) total value locked according to DefiLlama, second among chains behind Ethereum's $48.82 billion. Applications settling that value inherit the hosting concentration of the validator set, whether or not their users are aware of it.