The first time we had to shut down an Antminer we were pretty sure we flat out did it wrong. Since Bitmain’s ASICs (at least the S9, A3 and L3+) don’t have a power switch, the answer to shutting it down for us, and like many cryptocurrency miners, was just unplugging the power supply. We figured there had to be a way to safely shut an Antminer down. We had to poke around a bit, but it turns out there is.
Hot ASIC miners
Antminers run hot which is why those high RPM fans are bolted on to both end of the Chinese workhorses. While the unit is mining the fans force cooler air into one end of the ASIC. As the air passes through, it absorbs heat inside the unit, expelling it out the opposite.
What happens when you unplug an Antminer?
When you unplug a running Antminer there’s no power to the unit whatsoever. Obviously it drops it’s Internet connection, stops doing anything useful and becomes a paperweight. When it does so there is a bit of a potential concern, however.
No power means those fans on either end of the unit’s aren’t doing anything either. That leaves the chips inside to cool down on their own. Resident heat does make it’s way out by way of heat sinks, the limited air movement in the tube and the aluminum enclosure. But, it’s absolutely possible that before any cooling begins temperatures rise for a short period of time. That creates an opportunity for damage. Damage means bench time for the miner and loss of revenue.
What happens when you change an Antminer’s settings?
You’ve probably noticed that when you’re under or overclocking your S9, A3 or L3+ that the fans run at a very high RPM after you apply a frequency change. At this time the unit stops mining and ramps up the fans to continue moving heat off the boards and chips to prevent damage. The fans then spin down to a low level and the frequency change is applied over a minute or so in steps.
This is a logical way to power off a hot piece of sensitive hardware. We just need to stop mining but continue to run the fans for a bit. Here’s how.
Safely shut down an Antminer
You will need to know the local IP address of your Antminer as well as your login credentials to it’s dashboard and access to a computer on the same network. For this example we’re going to act like our Antminer is on a local network at the IP address 192.168.7.125 and that our administrator name is still set to root.
- Open the Terminal App (on a Mac) or Command Prompt (on a PC)
replacing root with your administrator name and 192.168.7.125 with the Antminer’s IP address
- If you get a security warning, such as an OS X host authenticity warning go ahead and still connect
- Provide the Antminer with your password when prompted
- You’re now connected to the Antminer. To stop mining but leave the fans running, type:
- The Antminer will respond letting you know it is shutting down.
- Wait five or ten minutes and then safely unplug the Antminer.
That’s it. Here’s what we did. First, in steps 1 through 4 we connected to and authenticated access to the Antminer. In step 5 we stopped the process of mining. Since the Antminer is stilled connected to its powersource the fans continue to cool the chips inside. Finally, once things have cooled down for a bit we unplug the Antminer knowing that there’s no chance of a temperature spike.
Most people will still likely just pull the plug. But, if you prefer to shut down your Antminer in a way less prone to damage, now you know how.