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The Solana network is experiencing a deep freeze, causing a near-complete shutdown of activity on the blockchain. Validators running Solana's infrastructure are preparing a second restart attempt to restore service to users of the blockchain. A first attempt was abandoned when validators realized they had chosen the wrong point to restart, leading to further delays. The problems started as sluggish transaction processing and have now resulted in a situation where transactions are not processing or being validated, and users' on-chain crypto assets are frozen in place until critical backend infrastructure comes back online.
Several theories are being explored as to the cause of the issue, with a leading theory being that a "fat block" has gunked up the blockchain's mechanics. Notably, the network was moving to an upgraded version shortly before its troubles began.
Validators and developers at Solana Labs are working to restart the chain, with some 70% of total stake behind the move. However, the network needs an 80% supermajority to proceed. The situation is ongoing, and it remains to be seen when the Solana network will be fully operational again.