Bitcoin Knots
Run a BLAKE2b node if you intend to mine this chain. Bitcoin Knots is the recommended node: it combines a full node and wallet, and it gives miners fine control over how block templates are constructed. Source is at github.com/bitcoinknots/bitcoin.
Bitcoin Core and older Knots releases still use the legacy SHA256d algorithm and will follow a different blockchain. You need a Knots version that includes the BLAKE2b change. See what this means for node operators.
What DATUM is
DATUM stands for Decentralized Alternative Templates for Universal Mining. Early Bitcoin treated the person running a node as the miner: that machine chose the payments and submitted the block. Pools later started building the block themselves so many miners could share luck and get steadier pay. The hardware still hashes. The pool decides what goes in the block. When a handful of pools pick every payment, they can stall or drop ones they dislike.
DATUM reverses that. The DATUM Gateway asks your local node for a block template, sends work to your hardware, and submits a found block from that node. The person running the node is the miner. The gateway and the node can share one machine.
You can still smooth income through a DATUM-supporting pool. The pool only records how the block reward is split so people can share it. It does not build the block, and it does not hold the coinbase. Payouts can go straight to the miner. The work your hardware sees still comes only from your node, which is why Knots matters: you choose transactions there.
- Talks to a local node over RPC using
getblocktemplate. - Talks to hardware over Stratum v1, including version rolling.
- Talks to a pool, if you use one, over the DATUM protocol, which is a purpose-built link and not a Stratum v2 add-on.
- Supports Bitcoin only. Choose transactions on the node; the pool does not hand you a ready-made block.
While limits on arbitrary data storage are in effect, a block may also be no larger than about 300 kB (700,000 weight units). getblocktemplate reports that as weightlimit. Do not point the gateway at a 4,000,000-weight policy and expect those templates to be valid.
BLAKE2b mining
SHA256d mining against an ordinary getblocktemplate node needs no node source changes. BLAKE2b header-v2 mining, including Antminer A3 and other Sia-style BLAKE2b hashers, needs a Knots node built with the BLAKE2b proof-of-work change. Set mining.pow_algorithm to blake2b in the gateway config:
"mining": {
"pow_algorithm": "blake2b",
"allow_hasher_time_rolling": false
}Build and configuration details are in the DATUM Gateway repository.