Mining Academy
Antminer S19 and S21 BTC Pool Setup Step by Step
To set up an Antminer S19 or S21 on a Bitcoin pool, find the device's IP address, log in to the web interface, open Miner Configuration and enter stratum+tcp://enter.rupool.pro:3333 as the first pool URL, subaccount.worker as the worker and any character as the password. After you save, the miner restarts and shows up in your dashboard within a few minutes. The rest of this guide covers the interface, operating modes and temperature.
How S19 and S21 differ for pool setup
For pool connection, the S19 family (S19, S19 Pro, S19j Pro, S19 XP and related models) and the S21 family are nearly identical: both run SHA-256, both connect to the BTC stratum and both are configured on the same web page. The differences lie elsewhere. The S21 is considerably more energy efficient and usually ships with newer firmware, which may offer more built-in operating modes. Exact hashrate, power and efficiency differ between variants, so rely on the sticker on the case and the datasheet of your exact model.
If you are still choosing a model, compare efficiency in joules per terahash against your electricity price and run the options through the profit calculator. This guide is about launching a device you already have.
Step 1. Cabling and finding the IP address
Connect power (S19 and S21 draw several kilowatts; line requirements are in the power section below), plug an Ethernet cable into your router or switch and power on. The control board boots in a couple of minutes, after which the fans settle at working speed.
The router usually assigns the address via DHCP. You can find it three ways:
- in the router's client list, by device name or the MAC address printed on the sticker;
- with Bitmain's IP Reporter: press the IP Report button on the control board and the tool shows the address;
- with a network scanner such as Advanced IP Scanner if you have no router access.
On a multi-device farm it helps to reserve addresses by MAC in the router's DHCP settings: IPs then survive reboots and you always know which device sits where.
Step 2. Log in to the web interface
Enter the IP in a browser. On stock Bitmain firmware the default credentials are typically root / root, but batches and firmware versions vary, so check the documentation. After logging in, change the password immediately: an open admin panel on your LAN is a pool-hijack risk. If the device runs third-party firmware (Braiins OS+, VNish and others), the interface and menu names differ, but the pool fields are the same.
Step 3. Miner Configuration and pool fields
Open System, then Miner Configuration (menu names vary slightly between firmware versions). You will see three blocks, Pool 1, Pool 2 and Pool 3, each with URL, Worker and Password. Fill them as follows:
| Block | URL | Purpose |
|---|---|---|
| Pool 1 | stratum+tcp://enter.rupool.pro:3333 | primary |
| Pool 2 | stratum+tcp://enter.rupool.pro:8888 | fallback on another port |
| Pool 3 | stratum+ssl://enter.rupool.pro:999 | fallback over an encrypted channel |
In the Worker field use the same login in all three blocks, for example myfarm.s21_01, where myfarm is your RuPool subaccount and s21_01 is the worker name. The password can be anything, such as x. Worker names accept Latin letters, digits and underscores. If you want a specific region rather than auto-select, replace enter.rupool.pro with msk2-ru.enter.rupool.pro (Moscow), nsk-ru.enter.rupool.pro (Novosibirsk), hel-fi.enter.rupool.pro (Helsinki) or ala-kz.enter.rupool.pro (Almaty). Fallback TCP ports for BTC are 8888, 443 and 25.
Click Save & Apply and the device restarts the mining process. The general approach for any ASIC is covered in how to connect an ASIC to a pool, and the coin overview is on the BTC pool page.
Step 4. Checking status and the first hour
Open the Miner Status tab and look at:
- Pool status Alive on the first pool, meaning the connection is up;
- Accepted and Rejected shares. A small rejected share is normal; a large and growing one calls for checking your network and region;
- Hashrate (RT), the real-time value, which takes a few minutes to reach nominal as the hashboards warm up;
- Temperatures and fan speeds, discussed below.
At the same time open your pool dashboard. The worker does not appear instantly, and because the pool estimates hashrate from accepted shares, short-interval numbers bounce around. Judge by several hours of data. To let someone view statistics without access to your settings, create a watcher link.
Modes, frequency and power consumption
The principle is simple: a higher chip frequency gives more hashrate, more power draw and higher temperature, usually at worse efficiency in joules per terahash. A lower frequency gives less hashrate but better efficiency and less heat. Power-saving modes are built on exactly this.
- Stock Bitmain firmware. Newer firmware for current models may offer a choice of operating mode, for example normal, sleep or low power. The exact options depend on the model and firmware, so see what your unit offers. On older S19 firmware there is no direct frequency control.
- Third-party firmware (Braiins OS+, VNish, LuxOS and the like) lets you set a power limit or frequency precisely, adds auto-tuning and extra protections. The efficiency gain is usually noticeable, but the firmware is your risk: check compatibility with your board revision and keep warranty terms in mind.
Do not chase frequency on weak cooling or unstable power. Overclocking for a few percent of hashrate often ends in overheating, more hardware errors and lower earnings in the end. On the other hand, lowering the power limit when electricity is expensive can be economically justified. Compare both options in the calculator with your price per kWh.
Temperature, cooling and power
Miner Status shows board and chip temperatures. On air-cooled S19 and S21 units, chip temperature in operation is well above inlet air temperature, and the allowed limit is given in the documentation. If the device hits protection it lowers power or stops. Practical rules:
- Airflow. The unit takes air in on one side and exhausts on the other. Do not put it against a wall and do not aim the exhaust at a neighbor's intake.
- Room temperature. The hotter the inlet air, the hotter the chips. In summer, in a closed room with no exhaust, an ASIC reaches its limit quickly.
- Dust. Clogged heatsinks are the most common reason for temperatures creeping up over months. Blow them out regularly.
- Fans. Leave fan control on automatic. If you reduce speed for noise, test it over several hours.
- Electrical supply. S19 and S21 units draw several kilowatts at 220 to 240 V. They need a dedicated line of adequate cross-section, good sockets and connectors, a breaker with margin and ideally metering. A poor contact in a socket is a leading cause of melted connectors.
Within temperature limits the ASIC runs stably, but watch the trend: if hashrate declines over weeks at the same settings, dust, room temperature or worn fans are the usual causes.
Common problems after setup
- Pool Dead. Check address and port, the device's internet access, gateway and DNS. If 3333 is blocked, try 443 or SSL 999.
- Worker missing in the dashboard. Check the subaccount spelling and the dot between it and the worker.
- Hashrate below nominal. See whether all three hashboards were detected, whether temperatures are high and whether a low-power mode is on.
- Web interface will not open. Confirm you are on the same network and that the address did not change after a router reboot.
FAQ
Are pool settings the same for S19 and S21?
Yes. Both run SHA-256 and connect to the BTC stratum on port 3333 (or 999 for SSL). What differs is operating modes and firmware options.
Can I use an SSL connection?
Yes, stratum+ssl://enter.rupool.pro:999 works for BTC. It makes a good backup pool, or a primary one if your ISP interferes with plain TCP traffic.
How should I name a worker?
By location and device number: rack, row or a serial number. Naming schemes are covered in the article on worker names.
Do I need to change the factory password?
Yes. It is the most important thing to do after the first login, since web interface access lets someone change the pool and redirect your hashrate.
Stock or third-party firmware?
It depends on the goal. Stock is simpler and keeps the warranty. Third-party gives flexible power tuning but demands care. Start with stock and switch only when you understand why.