Mining

A miner is a hotkey registered on a subnet, doing whatever work that subnet's incentive mechanism rewards. The chain side of mining is small: register, tell validators where to reach you, and don't get evicted. The work itself — the model, the service, the actual commodity — is defined by each subnet's own codebase, not by the chain.

Registering costs the subnet's floating registration price, and what that payment buys depends on the subnet's configuration:

• On most subnets the whole price is burned — a sunk, non-refundable entry fee. See registration burn.
• Subnets can instead lock a share of the price as collateral — stake attached to your hotkey that you earn back by mining. See registration collateral. Some also ask for extra deposits via add_collateral and a floor via set_min_collateral.

Mining (and validating) is not supported on Windows. Wallet operations work under WSL 2, but run miners on Linux or macOS.

1. Scope the subnet

btcli subnets list
btcli subnets show 1
btcli query burn --netuid 1 --json                     # current registration price
btcli query subnet-hyperparameters --netuid 1 --json   # immunity, limits, collateral_*
btcli query collateral-policy --netuid 1 --json        # lock share + drain ratio only
btcli query metagraph --netuid 1 --json                # who you're competing with

Choosing where to start matters more than the registration price. Eviction only happens when a subnet is at capacity, so an under-capacity or new subnet lets you learn without deregistration risk; a mature high-emission subnet means competing against miners tuned over months. Each subnet's repo conventionally documents hardware needs (min_compute.yml or the README), and most subnets run on a testnet netuid — test there or on a local chain before paying the registration price.

Check the subnet's collateral policy before budgeting: collateral_lock_share (also on subnet-hyperparameters / collateral-policy) tells you what fraction of the price is a recoverable lock rather than a burn.

Note also whose hotkey you register: mining on the subnet owner's hotkey (or its associated hotkeys) is pointless — miner emission directed at owner-associated hotkeys is never paid out, it is burned or recycled (burned by default, per the subnet's RecycleOrBurn setting).

2. Register

burned-register charges the subnet's current registration price from your coldkey and assigns your hotkey a UID:

btcli tx burned-register --netuid 1 --dry-run -w my_coldkey
btcli tx burned-register --netuid 1 -w my_coldkey

price = await client.subnets.burn(netuid=1)   # current registration cost
await client.execute(bt.BurnedRegister(netuid=1), wallet)

The UID goes to the wallet's hotkey by default; pass hotkey_ss58 to register a different one.

Registration is continuous — there are no registration windows. Admission is governed entirely by the dynamic price described in registration burn: it decays every block and jumps after every successful registration, so a rush gets expensive fast. The cost floats and is only known at execution time, so a configured Policy spend cap blocks this call until raised.

Confirm with uid or netuids-for-hotkey. One hotkey can hold UIDs on multiple subnets simultaneously, but only one UID per subnet.

3. UID capacity and eviction

A subnet has a fixed number of UID slots: default 256, owner-trimmable down to a floor of 64. When the subnet is full, each new registration evicts one existing neuron — the one with the lowest pruning score that is not immune. The rules, as implemented in the chain's pruning logic:

• The pruning score is emission-based. The chain does not distinguish miners from validators when pruning; whoever earns least is first out.
• Immunity is (current_block - registered_at) < immunity_period. The chain default is 4096 blocks (about 13.7 hours at 12-second blocks), but real subnets often set it much higher — read the actual value with immunity-period before you plan around it.
• If every neuron is still immune, the lowest-scoring immune neuron is pruned anyway; immunity is a preference, not a guarantee.
• Ties on pruning score evict the older registration first.
• The subnet owner's hotkey is permanently immune (bounded by an owner-immune limit, default 1 hotkey).

Practical consequence: your immunity period is your runway. If the subnet's immunity_period is 4096 blocks, you have about half a day to start earning emissions before you're evictable.

Eviction is mechanical, not a judgment. It costs you the UID and nothing else: your stake stays where it is, and on a collateral subnet your locked collateral stays attached to the hotkey and is credited when you re-register.

4. Publish your endpoint

Validators find you through the axon info stored on chain. serve-axon writes your ip:port; it does not start a server — running the actual service is your job:

btcli tx serve-axon --netuid 1 --ip 203.0.113.7 --port 8091 -w my_coldkey -H my_hotkey

Use serve-axon-tls if peers should verify a TLS certificate, and reset-axon to stop advertising. Re-publishing is rate-limited by the chain.

Moving to another machine: start the miner on the new machine and publish the new axon first, wait until the old machine stops receiving validator requests, then stop it. Validators take time to pick up an updated IP.

All miner traffic comes through validators — only they can score you, so there is no reason to serve anyone else. Requests transit validators and miners with no confidentiality guarantee in either direction; subnets are not a channel for private data.

5. Watch your standing

btcli query metagraph --netuid 1 --json     # your rank, incentive, emission
btcli query blocks-since-last-update --netuid 1 --uid 0 --json
btcli query immunity-period --netuid 1

Expect discovery lag. Emissions are credited at tempo boundaries (default tempo 360 blocks, about 72 minutes), and validators typically refresh their metagraph periodically rather than every block — a freshly registered miner can sit at zero for a while before validators start querying it. That lag is exactly what the immunity period is for.

When the subnet runs commit-reveal, add the reveal period to every number you watch: validator scores on chain are stale by that window, so do not use your on-chain score as a liveness signal — by the time it drops, the failure is old and deregistration is likely already unavoidable. Monitor your own service directly.

Longevity compounds. Validators' bonds toward a miner build up as an exponential moving average, so an established miner out-earns an identical newcomer until the newcomer's bonds mature — see emissions for the bond math. On collateral subnets, longevity also pays down your lock: every alpha of incentive you earn releases collateral back to withdrawable stake.

Rewards accrue to the hotkey as stake. Have them auto-staked to a hotkey of your choice with set-auto-stake.

Key hygiene

• Sign operational calls with the hotkey; keep the coldkey off the mining box entirely. Mining stacks pull in large untrusted dependency trees (ML frameworks, model code), and any of it could exfiltrate a key file — see wallets for the coldkey/hotkey split. Use a proxy if the box must submit coldkey-signed calls.
• Create hotkeys on a trusted machine and transfer only the hotkey file (or mnemonic) to the miner.
• If the hotkey is compromised, swap-hotkey replaces it while keeping its registrations — and, on collateral subnets, its locked collateral, which follows the hotkey.