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Key takeaways
- On October 21, 2026, Solana switched its consensus system to Alpenglow, which targets finality of about 150 milliseconds instead of 12.8 seconds. The Solana Foundation says users need to take no action.
- On October 22, Ethereum developers postponed Glamsterdam's October 26 activation on the Hoodi test network to investigate how a gas-pricing change interacts with smart contracts already on mainnet. No new date is set.
- Neither change asks anything of ordinary holders. Anyone who tells you to "upgrade," "migrate" or "swap" your SOL or ETH because of an upgrade is running a scam.
Two of the biggest blockchains made upgrade news this week, in opposite directions. Solana switched on a new way of agreeing on transactions, and Ethereum hit pause on a test of its next upgrade after security researchers raised a concern. If you simply hold SOL or ETH, neither one asks anything of you.
Solana: Alpenglow is live
On Wednesday, October 21, 2026, Solana's validators retired TowerBFT, the consensus system the network had used since it launched in March 2020, and switched to Alpenglow. Anza, the engineering firm that built it, calls it the network's largest consensus upgrade since launch.
The headline change is speed to finality, the moment a transaction becomes permanent and can't be undone. The Solana Foundation says that used to take about 12.8 seconds and Alpenglow targets roughly 150 milliseconds. CoinDesk notes that 150 milliseconds is a goal under normal conditions, not a promise for every payment, and that how fast you see it also depends on the app or exchange you use.
How it works, in short: validators used to vote by sending transactions, and a block became final once enough votes stacked up. Now votes go directly from validator to validator and are combined into certificates, which lets a block reach finality within one or two voting rounds.
- What doesn't change: the Foundation says transaction formats, fees, programs and wallets work as before. Its message to users is "No action needed."
- One thing you may notice: validator votes no longer show up as transactions in blocks, so dashboards that counted them will show lower transaction totals. CoinDesk points out that a sharp drop on a chart can reflect this change rather than less real use.
- Still to come: a second phase, Rotor, will change how block data spreads across the network. The Foundation says it isn't scheduled yet.
Ethereum: the Glamsterdam test is on hold
Glamsterdam is Ethereum's next planned hard fork. It activated on Sepolia, one of Ethereum's test networks, on October 6, and its next rehearsal was set for the Hoodi test network on October 26. On October 22, the Ethereum Foundation said that activation is postponed, with no new date. Developers want more time to study how one proposal, EIP-8037, interacts with smart contracts already running on mainnet. A planned increase in Hoodi's gas limit to 200 million is postponed with it.
The concern came from the security firm ChainSecurity. In an October 13 analysis, it showed that two Glamsterdam proposals, EIP-8037 and EIP-8038, change how gas is charged and refunded. Some contracts rely on a failed call leaving too little gas for anything else to happen, so the whole transaction reverses. Under the new rules, ChainSecurity found, a failure that used to undo everything could instead be recorded permanently. Cointelegraph gives an example: a contract could remove a user's claim or block a retry on an operation that should have succeeded.
Cointelegraph reports that ChainSecurity later said it had found 13 real-world examples and was privately alerting the projects involved. CoinDesk notes that the firm has not publicly shown a major live protocol to be exploitable, and that the findings don't point to any contract being exploited through these proposed changes today.
What this means for you
- You don't need to do anything. The Solana Foundation says users need take no action for Alpenglow. The Ethereum Foundation says the Hoodi delay requires nothing from mainnet users or ETH holders.
- Faster settlement may show up gradually. Exchanges and shops that wait for finality can, in principle, credit Solana payments sooner, but each service decides how quickly to act on it.
- Read transaction charts with care. A drop in Solana's reported transaction count after October 21 may come from votes leaving the chain, not from fewer people using it.
- Upgrades carry risk. Big changes to core code can bring new bugs. Glamsterdam's pause is a reminder that a schedule is not a promise.
The takeaway
Solana's switch to Alpenglow, which Anza calls the most ambitious blockchain upgrade since Ethereum's Merge, happened without asking holders to lift a finger. Ethereum's pause shows the other side of upgrades: careful testing sometimes means waiting. Either way, the right move for an ordinary holder is to do nothing and ignore anyone who says otherwise. This is education, not financial advice, and it reflects the Solana and Ethereum Foundations' announcements and news reports as of October 23, 2026.
Frequently asked questions
Do I need to do anything with my SOL after Alpenglow?
No. The Solana Foundation says users need take no action: signing, sending and approving transactions work as before, and fees and wallets are unchanged. Validator operators had to update their software, and some data services such as indexers had to adjust how they read blocks.
Is my ETH at risk because of the Glamsterdam delay?
No action is needed. The Ethereum Foundation says the postponement concerns the Hoodi test network and requires nothing from mainnet users or ETH holders. The issue was found in proposed rules, before they reached mainnet.
What is finality?
Finality is the moment a transaction becomes permanent and can't be undone. Exchanges, merchants and apps often wait for it before treating a payment as settled.
When will Glamsterdam reach Ethereum mainnet?
No date has been set. The Ethereum Foundation says its postponement notice sets no mainnet date and that a new Hoodi schedule will come separately. Cointelegraph reports developers had planned to fix the mainnet schedule after successful Hoodi testing.
Sources
- Alpenglow (network upgrade page) (opens in a new tab) — Solana Foundation
- Alpenglow is Live on Solana: The World's Fastest Finality on a Global Network (opens in a new tab) — Anza (PR Newswire)
- Solana's biggest network change since 2020 is live. Here's how users benefit (opens in a new tab) — CoinDesk
- Glamsterdam on Hoodi Postponed (opens in a new tab) — Ethereum Foundation
- Glamsterdam Hard Fork: When Spent Gas Comes Back (opens in a new tab) — ChainSecurity
- Ethereum delays Glamsterdam test after security devs flag risk to existing contracts (opens in a new tab) — CoinDesk
- Ethereum delays Glamsterdam Hoodi testnet launch over security risks (opens in a new tab) — Cointelegraph (via TradingView)
Published October 23, 2026 by Dave McNaught. Educational content, not financial, legal or tax advice. Spot an error? Request a correction.
Dave McNaught
Dave McNaught has worked in IT since 1999 and founded All Business Technologies (ABT) in 2003, a Boston-area firm providing Managed IT, Cybersecurity, Managed AI, Web Design and App Development. He publishes The Crypto Guide.