A Teraswitch routing failure took 28.83% of staked SOL offline on Thursday, bringing Solana within 4.51 percentage points of its finality halt threshold. Under Solana's proof-of-stake consensus, finality requires more than two-thirds of stake to be actively participating; losing a third or more would prevent the network from finalizing blocks. Approximately 90 validators across Europe and Asia were affected, with more than 133 million SOL temporarily knocked offline. Affected validators lost an estimated 333 SOL in rewards, prompting Marinade Finance to announce a review of ASN and data center concentration risks.

Traffic returned at 04:16:15 UTC, according to Marinade Finance.

Teraswitch Routing Fault Hit Multiple Sites

According to Marinade, Teraswitch advertised a default route from its Miami site without the proper route attributes. A route reflector in Amsterdam then propagated that route to sites across Europe and Asia. Edge routers treated the 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, Marinade reported.

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

More Than 133 Million SOL Went Offline

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

Marinade could not establish whether those outages shared a common dependency. Fifty-nine validators holding 80.2 million SOL returned within the same narrow recovery window. Marinade noted that the validators did not fail over before routing recovered — a signal that automatic failover mechanisms either were not configured or did not trigger under these conditions.

Validators Lost 333 SOL in Rewards

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

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

The concentration figures underscore a recurring concern in proof-of-stake networks: while stake can be distributed across many validators, underlying infrastructure may still cluster around a small number of hosting providers and data centers, creating correlated failure risks that nominal validator counts can mask.

Marinade plans to review concentration limits by ASN and data center. The protocol also intends to publish information on whether validators use hot-swap and automatic failover systems.