Solana Near Finality Halt After Teraswitch Outage Affects 29% of Stake

• A Teraswitch routing failure took 28.83% of staked SOL offline, bringing Solana within 4.51 points of its finality halt threshold.
• About 90 validators across Europe and Asia were affected, with more than 133 million SOL temporarily offline.
• Affected validators lost about 333 SOL in rewards, prompting Marinade to review ASN and data center concentration risks.

Solana came within 4.51 percentage points of its finality halt threshold Thursday after a Teraswitch routing failure took 28.83% of staked SOL offline. The outage affected about 90 validators across Europe and Asia, while 94% of stake on AS20326 went offline simultaneously. Traffic returned at 04:16:15 UTC, according to Marinade Finance.

According to Marinade, Teraswitch advertised a default route from its Miami site without its route attributes. A route reflector in Amsterdam then passed the route to sites across Europe and Asia. Edge routers treated that route as local and preferred it over the valid default route.

However, Teraswitch’s core rejected the route as invalid, leaving 12 sites without a usable path. The affected locations included London, Amsterdam, Dublin, Frankfurt, Singapore and Tokyo. North American sites did not experience the same issue, according to Marinade.

Teraswitch identified the problem within 10 minutes. Traffic returned at 04:16:15 UTC, while Miami remained disconnected from its backbone during further checks.

Marinade found 118.89 million SOL on AS20326, equal to 27.34% of network stake. About 94% of that stake went offline during the incident. Another 14.1 million SOL went offline across Latitude.sh, Limestone, Butterfly Research and Allnodes.

Marinade could not establish whether those outages shared a dependency. Fifty-nine validators holding 80.2 million SOL returned within the same narrow recovery window. Marinade said the validators did not fail over before routing recovered.

Helius, Solana’s second-largest validator, remained offline for the full 33 minutes. Of 74 validators Marinade measured, Laine, Cogent Crypto, SOL Strategies and Lion3d recovered cleanly.

Marinade said four ASNs hold two-thirds of its allocated stake, with AS395201 alone holding 36.94%. The 90 affected validators lost about 333 SOL in rewards, covered by validator bonds at epoch end.

Marinade plans to review concentration limits by ASN and data center. It also plans to publish whether validators use hot-swap and automatic failover systems.