How to Solo Mine BCH with Antminer S21+

On May 9, 2026 at 23:30:03 server time, an Antminer S21+ (worker label: S21Plus01) on the SoloFury pool solved Bitcoin Cash block #950338. The coinbase transaction sent 3.0971 BCH directly to the miner’s wallet. Roughly $1,393 USD, no intermediary, no waiting period, no payout request. Just a wallet that woke up heavier than it went to sleep.

That happens about every 4-5 weeks for SoloFury’s house fleet of four S21+ rigs. Some weeks two blocks. Some weeks none. The math is real. And the setup that produced that block? It’s the same setup any individual miner can replicate at home or in a hosting facility. Single S21+, configured correctly, pointed at the right chain.

This is the gufo’s complete how-to. We assume you have the rig and want to point it at BCH for solo mining. We’ll cover the math (briefly), the wallet, the configuration, the monitoring, AsicBoost, heat, and what happens when the dashboard suddenly shows “BLOCK FOUND.”

Why BCH (and not BTC)

The most common mistake new solo miners make: they buy an S21+ and immediately point it at Bitcoin. Let’s run the numbers one more time so you can avoid this.

An Antminer S21+ delivers ~235 TH/s. Bitcoin’s network is roughly 750 EH/s. Bitcoin Cash’s network is roughly 4.5 EH/s. Same SHA-256 algorithm, same hardware, but the network sizes differ by a factor of ~167.

BCH is where one S21+ becomes a real solo mining proposition. Mean expected time of ~4-5 months for a $1,400 payout, on a chain with the same SHA-256 algorithm, mature liquidity, and broad exchange support. If you can run an S21+ for half a year of electricity ($300-600 depending on rates), the expected value is positive. The math works.

Multiply by 4-6 rigs and you’re looking at one block per month average. Multiply by 10 and you’re at biweekly. The variance is real, but so is the math.

What you need before you start

• The rig itself — Antminer S21+ (or S21, S21 Pro, S21 XP Hydro). 220V 30A circuit. Network cable.
• A BCH wallet — The wallet address is your miner’s identity. It’s where the block reward will arrive if you find one.
• Internet connection — Stable. Stratum doesn’t need much bandwidth (~1 KB/s) but needs uptime. Even a few minutes offline at the wrong moment costs you money.
• Cooling and ventilation — An S21+ outputs ~3,300 watts of heat. That’s a small space heater running 24/7. Plan ventilation accordingly.
• Sound tolerance (or distance) — S21+ runs at ~75-80 dB. That’s “lawnmower in the next room” territory. Most miners host them in a garage, basement, dedicated room, or third-party hosting facility.

Step 1 — Get a BCH wallet

Solo mining is non-custodial. The pool never holds your funds. The block reward is paid directly by the network, via the coinbase transaction, to the wallet address you configure as your stratum username. Wrong address = wrong recipient. Take this step seriously.

Recommended wallets for receiving BCH solo mining rewards:

Hardware wallets (recommended for serious miners)

• Ledger Nano S Plus / Nano X — Native BCH support via Ledger Live. Best balance of security and usability. ~$80-150.
• Trezor Model One / Model T — Native BCH support via Trezor Suite. Open-source firmware. ~$70-220.
• Coldcard Q — BTC-focused, but supports BCH via PSBT workflows. Air-gapped. For paranoid users.

Software wallets

• Electron Cash — The de facto BCH wallet. Open source, deterministic, works on desktop and mobile. Generates standard CashAddr addresses. electroncash.org
• Bitcoin.com Wallet — Mobile-first, supports BCH and BTC. Easy onboarding for newcomers.
• BitPay — Multi-coin wallet with hardware wallet integration.

Address format: Modern BCH wallets generate addresses in CashAddr format, starting with bitcoincash:q… or just q…. Older wallets may give you a legacy P2PKH address starting with 1…. Both work for receiving — most pools and miners now use CashAddr by default. SoloFury accepts both formats as stratum username.

Critical: Generate the wallet, write down the seed phrase on paper, store it offline. Verify you can restore the wallet from the seed before you start mining. If you find a block to a wallet whose seed you didn’t back up, and the device fails — the BCH is gone.

Step 2 — Configure your S21+

Access the miner’s web UI

Power on the S21+. Wait 60-90 seconds for it to boot and acquire a DHCP IP. Find its IP via your router’s DHCP lease table, or use Bitmain’s discovery tool (asic-tools), or check the static IP if you set one.

Open a browser to http://[miner-ip]/. Default credentials: root / root (Bitmain stock firmware). Change this immediately on first login.

Stratum configuration

Navigate to Configuration → Miner Configuration. You’ll see three pool slots (Pool 1, Pool 2, Pool 3 — primary and two failovers). Configure them as:

# Pool 1 (primary)
URL:      stratum+tcp://bch.solofury.com:7070
Worker:   YOUR_BCH_WALLET_ADDRESS.S21Plus01
Password: x

# Pool 2 (failover, second port)
URL:      stratum+tcp://bch.solofury.com:7071
Worker:   YOUR_BCH_WALLET_ADDRESS.S21Plus01
Password: x

# Pool 3 (failover, third port)
URL:      stratum+tcp://bch.solofury.com:7072
Worker:   YOUR_BCH_WALLET_ADDRESS.S21Plus01
Password: x

# European miners: use eu-bch.solofury.com for ~25ms latency
# Asia/Pacific: use asia-bch.solofury.com

Three things to get right:

1. Wallet address before the dot. This is where the BCH will go if you solve a block. Copy-paste it. Don’t type it. Verify the last 4 characters match.
2. Worker name after the dot. This is just a label. Use whatever helps you identify the rig in the dashboard. S21Plus01, basement-rig-1, antminer_top_shelf, your call.
3. Password = x. Yes, just the letter x. Stratum passwords are conventionally ignored on solo pools. Don’t overthink it.

Click Save. The miner will restart its mining process and connect to SoloFury within ~30 seconds. Watch the Status page; you should see “Mining” and a connection to bch.solofury.com.

Verify the connection from the pool side

Open solofury.com/miner/ in a browser. Paste your BCH wallet address into the search field. Within ~30 seconds your worker should appear with status ● ONLINE, hashrate climbing toward ~235 TH/s, and a small green dot next to the worker name.

If you don’t see the worker after ~2 minutes, double-check:

• Stratum URL is correct (no typos, no wrong port)
• Wallet address is correct (no extra spaces, no truncation)
• Network connection from miner is reachable (ping the miner from your PC)
• Firewall isn’t blocking outbound TCP on 7070-7072

Step 3 — Monitor your mining

Once you’re online, open the SoloFury miner dashboard and bookmark the URL with your wallet address as a query parameter:

https://solofury.com/miner/?addr=YOUR_BCH_WALLET_ADDRESS&coin=bch

This is your home base. Refresh interval is automatic (~30 seconds). The metrics that matter:

Status indicator

Green “ALL GOOD” = your worker is submitting shares and the pool is acknowledging them. This is what you want to see. If it goes red, something’s wrong — usually network connectivity.

Your Hashrate

Live (5-minute average) and 24-hour average. For a stock S21+, expect ~225-235 TH/s sustained. Spikes and dips of 5-10% are normal — that’s just sample timing, not actual performance variation.

Best Share

The best share you’ve submitted in the current “luck cycle.” When this hits or exceeds the network difficulty, you’ve found a block. Watch this number climb. It’s the most important number on the dashboard.

Network difficulty for BCH currently sits around 700-900G. You’re constantly submitting shares of various difficulties (most are at the pool’s vardiff target). Occasionally one of those shares is unusually difficult — that’s your “best share.” When the dice roll all the way to network difficulty, it becomes a block.

Network Share

What percentage of the BCH network you currently represent. For one S21+ on BCH (~4.5 EH/s network), expect around 0.005%. For four S21+: ~0.02%. For ten: ~0.05%. The bigger this number, the more often you’ll find blocks.

Net Difficulty

Current Bitcoin Cash network difficulty. This adjusts every block (BCH uses ASERT difficulty adjustment, which responds quickly to network hashrate changes). When difficulty drops, your odds improve. When it rises, your odds worsen. You can’t control it; you can only point your hashrate.

Step 4 — Enable AsicBoost

AsicBoost (version-rolling) is a protocol-level optimization that lets compatible ASICs hash slightly more efficiently. SoloFury supports it natively on the stratum server.

For Antminer S21+ on stock Bitmain firmware, AsicBoost is enabled by default if your firmware is recent (≥ 2024). To verify:

1. Web UI → System → Mining Status
2. Look for “Version Rolling” or “VR” indicator. If present and active, AsicBoost is enabled.
3. Check the SoloFury miner dashboard — under your worker stats, “AsicBoost: Yes” appears in some views (depending on stratum negotiation).

If you’re running BraiinsOS, VNish, or LuxOS firmware, AsicBoost is enabled by default and typically delivers ~5-12% efficiency gains over stock — meaning you get more hashes per watt, which improves both your odds (slightly) and your power bill (significantly).

Step 5 — Heat, power, and physical setup

An S21+ at full throttle produces ~3,300W of heat. In imperial units, that’s about 11,250 BTU/hour — comparable to a 1.5-ton residential heat pump. You will feel this in any small room.

Power requirements

• Voltage: 200-240V required (won’t run on standard US 120V outlets without a step-up transformer).
• Current: ~15A at 240V. Use a dedicated 30A circuit with a NEMA 6-30 or NEMA L6-30 outlet.
• PSU: Stock APW12 (3,300W rated). Don’t undersize.
• UPS: Optional but recommended for stable power. Even a small surge can soft-brick the control board.

Cooling

The S21+ has two 6,000 RPM fans pulling 200+ CFM of air through the heatsinks. Hot air exhausts from one end. Don’t put it in a closed cabinet. Don’t put it next to fabric or paper. Don’t run it in an attic in summer.

Acceptable hosting environments:

• Garage with ventilation (winter is fine, summer requires AC or careful airflow)
• Dedicated mining room with exhaust fan
• Basement with cool ambient temperature
• Third-party hosting facility (the gufo’s strong recommendation for 2+ rigs — typical rates $0.06-0.10/kWh, professional cooling, 24/7 monitoring)

Power costs

At 3,300W continuous and $0.10/kWh: ~$240/month. At $0.15/kWh: ~$360/month. At European rates of $0.30/kWh: ~$720/month. The break-even calculation for solo mining BCH:

Mean expected: 1 block / ~133 days at $1,400/block = ~$10.50/day expected revenue. So:

• $0.10/kWh: $7.92/day power → ~$2.50/day positive expected, slow ROI on $4k rig
• $0.15/kWh: $11.88/day power → roughly break-even on power alone
• $0.30/kWh: $23.76/day power → significantly negative expected unless price moves

European retail rates make solo BCH mining hard without subsidized power, hosting deals, or speculation on BCH price. This is why hosting facilities exist.

Step 6 — Optional: BraiinsOS or VNish firmware

Stock Bitmain firmware works, but custom firmware can squeeze more efficiency:

• BraiinsOS+ — Open-source, autotuning, sophisticated overclocking. Free to use; takes a small share of your hashrate as developer fee. Excellent for advanced users. braiins.com/os
• VNish — Closed source, autotuning, polished UI. Popular in the rental market. Small fee.
• LuxOS — Maintained by Luxor, focused on enterprise. Great telemetry, integrated with their pool but works with any stratum.

Typical efficiency gains with custom firmware: 5-15% better J/TH on the same hardware. That translates directly to lower power bills and slightly better expected value. For a single rig, you may not bother. For a fleet of 5+, custom firmware pays for itself within weeks.

What happens when you actually find a block

Sometime between hour 1 and year 1 of mining, your dashboard will look different. The “Best Share” suddenly equals or exceeds the network difficulty. The pool log will record:

[YYYY-MM-DD HH:MM:SS] Solved and confirmed block 950338
                       by YOUR_WALLET_ADDRESS.S21Plus01
[YYYY-MM-DD HH:MM:SS] Block solved after 673885207470 shares at 91.6% diff
[YYYY-MM-DD HH:MM:SS] Submitting possible block solve share diff 2445462360340.071777 !

Within 10 minutes, the BCH network confirms the block. The coinbase transaction lands in your wallet. Within 1-3 confirmations, the funds are spendable.

The technical flow:

1. Your S21+ submits a share that satisfies network difficulty (cryptographically rare event).
2. SoloFury’s stratum server validates the share and assembles the block.
3. The block is broadcast to the BCH network via the SoloFury BCH node.
4. Network nodes verify the block, accept it, and start mining the next block on top.
5. The coinbase transaction (output [0]) sends the block subsidy + transaction fees to the wallet address you configured as your stratum username — directly, without intermediate custody.
6. SoloFury’s pool fee (1%) goes to a separate output [1] in the same coinbase TX.

Verify your block on-chain:

• blockchair.com/bitcoin-cash
• bch.loping.net
• 3xpl.com/bitcoin-cash

Look for the “SoloFury BCH” tag in the coinbase scriptSig (the human-readable text embedded by the pool). That’s your proof.

Troubleshooting

”My hashrate is lower than expected”

Stock S21+ should sustain 220-240 TH/s. If you’re at 180-200, possible causes:

• Voltage sag (PSU underspec, long power cable, shared circuit)
• Overheating (chip temp >85°C triggers throttling)
• Wrong frequency profile (check Configuration → Miner Configuration → Frequency)
• Hardware errors >2% (one or more hashboards degrading)

“I’m getting rejected shares”

Some rejected shares are normal — usually 0.1-0.5% on a healthy setup. Higher rejection rate suggests:

• Network latency to pool too high (try a closer regional server: eu-bch / asia-bch)
• Stale shares (your miner submitted work for an older block template; usually solved by closer servers or better internet)
• Miner clock drift (verify NTP is enabled in System → Time)

“Worker disconnects randomly”

Almost always a network issue. Verify:

• Stable wired Ethernet (don’t use WiFi for ASIC mining)
• Pool 2 and Pool 3 backups configured (so failover happens automatically)
• No QoS rules on your router throttling outbound TCP on stratum ports

”How long should I expect to mine before finding a block?”

Mean: ~133 days for one S21+ on BCH. Mean is not median — about 50% of miners find one within 92 days, but ~25% will wait longer than 184 days. If you’re at day 150 with no block, that’s still in the normal distribution.

Scaling up: more rigs, rental hashrate

Adding more S21+ rigs

Same wallet address, different worker names. Pattern:

Rig 1: YOUR_WALLET.S21Plus01
Rig 2: YOUR_WALLET.S21Plus02
Rig 3: YOUR_WALLET.S21Plus03
...

The pool aggregates all your hashrate under your wallet on the dashboard. Each rig submits independently but the block reward (when found) goes to the single wallet address. Scale: 4 rigs → ~1 block/month average. 10 rigs → ~biweekly. 20 rigs → ~weekly.

Renting hashrate

If you want a one-time burst of probability without buying hardware, MiningRigRentals lets you rent SHA-256 hashrate by the hour or day. Point the rental at SoloFury’s BCH stratum, use your wallet address as the username, and the math works the same as owned hardware.

Rough costs: $50-100 buys you ~1 PH/s for 24 hours. That’s 4-5x the hashrate of a single S21+. Daily probability on BCH: ~3.2%. Roughly 1 in 31 chance of finding a block in 24 hours. Repeated rentals give cumulative odds. Used strategically (during low difficulty windows, for example) it’s a legitimate edge.

For miners without their own hardware: this is the non-custodial way to participate. Your hashrate, your wallet, full block reward if you hit. Sign up at MiningRigRentals.

The gufo’s parting wisdom

Solo mining BCH with an S21+ is one of the rare cases in the cryptocurrency space where the math actually rewards the patient operator. Real expected value, real timeline, real chain liquidity. No NFT hype, no validator games, no governance theater. Just SHA-256, electricity, and time.

Set it up correctly. Verify the wallet address three times. Configure the stratum carefully. Monitor occasionally but don’t obsess. Variance will give you stretches of nothing followed by abrupt jackpots. That’s the whole game.

And when you find your first block — and you will, eventually, if you keep at it — you’ll understand why some of us have been doing this for years. The math is patient. The network doesn’t care. But the network does pay, in full, every time the dice roll your number.

The owl that returns to the same field every night, and waits, and watches — that owl knows when the field will deliver. The S21+ is your eyes. BCH is the field. The dice are already rolling.