Solana prepares for Alpenglow consensus upgrade to slash finality times
Solana's core consensus upgrade, Alpenglow, is scheduled to activate on mainnet-beta on Oct. 21, replacing TowerBFT to reduce transaction finality to roughly 150 milliseconds.
Solana is preparing to activate its major consensus protocol upgrade, dubbed Alpenglow (SIMD-0326), on mainnet-beta on Wednesday, Oct. 21 at approximately 14:00 UTC during Epoch 1064. According to developer group Anza, the migration is scheduled to take effect in a single slot at migration boundary 459,653,000. The upgrade marks the retirement of TowerBFT, which has anchored Solana's consensus since March 2020.[4][3][5]
The Alpenglow transition is designed to significantly improve network speed and resilience. Community outlet SolanaFloor reported that the new consensus is expected to accelerate transaction finality by roughly 85 times, cutting confirmation windows from around 12.8 seconds to approximately 150 milliseconds. Additionally, network fault tolerance will increase from 33% to 40%, while validator votes—which made up about 56% of all Solana transactions in early October—will move offchain, freeing block space for users.[3][5]
By the evening of Oct. 20, over 90% of validators met all prerequisites for the upgrade. Earlier tracker data from Pumpkin's Pool showed that 151 validators holding 20.3% of network stake (88.9 million SOL) had remained unprepared roughly one day before activation. Anza and the Solana Foundation warned that validators failing to upgrade to Agave 4.3.2, configure an active BLS key, and fund their vote accounts with 0.8 SOL will be automatically blocked from voting and producing blocks once Alpenglow goes live.[1][2][3][5]
Key facts
- Solana's Alpenglow upgrade is scheduled to activate on mainnet-beta on Oct. 21 at approximately 14:00 UTC at Epoch 1064, migration boundary 459,653,000.
- Alpenglow replaces TowerBFT, which had operated Solana's consensus protocol since March 2020.
- The upgrade is set to reduce transaction finality by about 85 times, from 12.8 seconds to roughly 150 milliseconds.
- Solana's fault tolerance will rise from 33% to 40% under the new consensus mechanism.
- Validator votes, previously accounting for roughly 56% of transactions in early October, will move offchain to free block space.
- Over 90% of validators met the requirements for the upgrade ahead of activation.
- Pumpkin's Pool data recorded 151 validators with 20.3% of stake (88.9 million SOL) as unprepared about a day prior to the switch.
- Validators must run Agave 4.3.2, use an active BLS key, and fund vote accounts with 0.8 SOL or face automatic exclusion from voting and block production.
Sources · 4 sources
- BS
BSCN@BSCNewsPost on X ·
Solana validators still aren't ready for the Alpenglow upgrade! Statistics from @pumpkinspool show that 151 validators hold 20.3% of the network stake, worth 88.9M $SOL, and are not prepared for Solana’s Alpenglow hard upgrade, set for epoch 1064. Developers at @anza_xyz and the Solana Foundation released important advisories stating that unmigrated validators will be automatically blocked from voting and block production once the upgrade occurs. The Alpenglow boundary transition requires all validators to migrate to the Agave 4.3.2 client, use an active BLS key, and fund each vote account with 0.8 $ SOL.
Open source - SO
SolanaFloor@SolanaFloorPost on X ·
🚨JUST IN: With about a day until @Solana’s Alpenglow activation, 151 validators holding 20.3% of the stake remain unprepared. @anza_xyz and the Solana Foundation are urging validators to prepare for the switch, as those without Agave 4.3.2, a BLS key, and sufficient vote account funds will stop voting and producing blocks after activation. Data by @pumpkinspool
Open source - SO
SolanaFloor@SolanaFloorPost on X ·
🚨NEW: @Solana's biggest consensus upgrade, Alpenglow, will activate in under 19 hours, with over 90% of validators now meeting all requirements for the switch. The new consensus would make Solana transaction finality 85× faster, cutting it from around 12.8 seconds to 150 milliseconds.
Open source - CB
Crypto Banter@crypto_banterPost on X ·
🚨SOLANA IS GETTING MUCH FASTER TOMORROW! @anza_xyz confirms Alpenglow is pending activation on Solana mainnet-beta and goes live tomorrow, Wednesday, Oct 21 at ~14:00 UTC. The upgrade activates in one slot at migration boundary 459,653,000, after which TowerBFT retires. The shift brings significantly faster finality to the network. A 24-hour countdown starts soon.
Open source - SS
SolanaNews.sol@solananewPost on X ·
🚨BREAKING: @ANZA_XYZ’S ALPENGLOW GOES LIVE ON SOLANA MAINNET IN UNDER 18 HOURS!🚨 Finality drops from 12.8 seconds to around 150 milliseconds, roughly 85x faster. Fault tolerance rises from 33% to 40% (making Solana more resilient to outages). TowerBFT has run Solana since March 2020. Tomorrow it’s replaced by the biggest consensus upgrade in the network’s history. Validator votes, about 56% of all Solana transactions in early October, move offchain, freeing up block space for real users. Over 90% of validators now meet every requirement for the switch, with activation set for epoch 1064.
Open source