ANTMINER S21 / INSTALL OR UPDATE

Your S21 is ready
Which command comes next?

You have the miner and a firmware package. The next choice depends on what is running now. Find your starting state below and go straight to the matching next step

2026-10-03 · VNISH Ninja

What is running on your S21?

Use this page for the base S21 with its AML board confirmed. If the model or board is uncertain, start with the fourth card

01 / FIRST INSTALL

Bitmain stock, with its build date confirmed

If the exact stock date is before 1 August 2026, open our S21 AML route and complete its checks. In Toolkit, the first-install command is Install firmware

Open the S21 installation route

02 / UPDATE

VNISH is already running

Use Update firmware for an existing VNISH installation. Confirm the device, running version and selected package before starting. An update is not a reason to return to stock first

Open the S21 update route

03 / CONFIRM THE BUILD

Stock date unknown, or 1 August 2026 onward

These starting states are outside our standard first-install route. Send us the exact S21 model, board and stock version so we can identify the next step. If another custom firmware is running, contact us first through the same support link instead of choosing Install or Update from this page

Confirm installation with us

04 / CONFIRM THE DEVICE

The label or board does not match

S21 Pro, XP, Hydro and Immersion are not alternate names for the base S21. If your board is not confirmed as AML, settle the model and board before selecting the package

Match my model and board

The command changes, the file checks stay

Get the package from the S21 page on this site and keep its original archive and filename
In Toolkit, Firmware name is vnish. Firmware version comes from the selected filename without its leading v
Select the folder containing the tar.gz, not the archive in the stock Bitmain web updater
Start with one miner, follow Operations to completion, then check the running version, cooling and accepted pool work

Questions and answers

Do I need a different S21 package for Install and Update?

For the confirmed S21 AML route, our current installation policy uses the same matching published package for those two commands. The starting firmware determines which command to choose

Does a stock date before August 2026 guarantee installation?

No. It places the date inside the standard route, but the exact model, board, access and package still need to match. Use the checks on the S21 installation page

Does an AML board always need USB unlocking first?

No. USB recovery is a separate board-specific procedure. It is not a blanket prerequisite for the network installation route

Catalog checked 2026-10-03

S21 firmware downloads Find my VNISH route