Zombie Miner
A zombie miner is an ASIC that is powered up and looks like it works while it does no useful work: hashrate is zero or it never reaches the pool.
What a zombie miner is
The word came out of site practice, where asics stand in rows. Fans hum, indicators glow, the meter winds up kilowatts, and in the pool statistics the worker says nothing. From the outside such a miner is alive, for your income it is dead, and that is where the name comes from.
The causes fall into two camps. The first is the link: the network went away, pool settings got lost, a switch dropped off. The asic keeps spinning its fans and heating the room while the work goes nowhere. The second camp is hardware: a dead control board, a stopped fan that tripped protection, failed hashboards.
The most galling variety is the partial zombie. One hashboard out of three stops answering, the asic runs and pays, yet it brings in about two thirds of what it used to. In the statistics that reads as things got worse, and on a site of ten miners it can easily go unnoticed for a month.
The economics here are simple and unpleasant. An Antminer S21 eats 84 kWh a day, which is about 11 euros on the Spanish rate. A zombie asic burns that money in full and returns zero, while a partial zombie returns two thirds against the full electricity bill.
Quick reference table
| What it is | the asic looks like it works and brings no income |
| Full zombie | the worker is quiet, hashrate is zero |
| Partial | a third of the hashrate gone at full draw |
| First cause | the network and the pool settings |
| Second cause | the control board, a fan, the hashboards |
How to catch them before the bill tells you
Turn on pool alerts for a quiet worker with a threshold of about fifteen minutes. It is free, and it turns a week of zombie into a twenty minute incident.
Watch the daily hashrate of every worker rather than the combined total. The total across ten asics hides a third lost on one of them, while a separate chart shows it right away.
On a site a PDU with metering per outlet helps: a sagging draw on one asic means a dead hashboard before the pool shows anything. Readable worker names like rack1-05 save you time hunting for the miner on foot.
An example from the bench
A client notices from the electricity bill that for a month he paid as if for six asics while income came in as from five. We look worker by worker: one miner had been quiet for three weeks because of a switch port. The loss is about 330 euros of electricity plus the revenue missed. Pool alerts take five minutes to set up and cost nothing.
Related terms
Where to go next on the site
Hardware
- Antminer S21 tool
- ASIC Miner knowledge base
Software
- Software firmware
Numbers
Questions and answers
How can you tell an asic is a zombie
By the pool rather than by the noise. The worker is quiet, or its daily hashrate sits well below the spec figure while draw at the outlet looks normal.
The asic is loud, so it must be working
It must not. When the link drops the fans keep spinning while no shares reach the pool. Check the pool statistics rather than the lights on the case.
Why does losing a third of the hashrate stay invisible so long
Across several asics the combined chart smooths the dip out. You have to look at individual workers, and better with alerts.
What should you check first
The network: cable, port, pool address and port. Then power, then the count of live hashboards in the asic interface.
How the terms connect
Every link in the chain is clickable. Orange marks where you are now.
Looking for an ASIC miner
The catalog holds 212 models. You can compare them by hashrate and by joules per terahash, then plug your own rate into the calculator and see what stays in your pocket.
Page written and checked by Denys Klimchuk. Updated .