Kev's Development Toolbox

Updated: 1/30/18: Thanks to Max for the comment asking how your wallet id is passed to the miner – the Kubernetes deploy yml file example was cut off at the end and missing the args. Updated the example to show the correct args passed, including your wallet address.

Disclaimer: I don’t claim to be an expert in crypto currency and/or mining, my interest is purely a curious interest in the technology. Please don’t interpret anything here as an endorsement or a recommendation. Is it profitable to mine any currency with a spare PC? Probably not. Are some currencies profitable to mine? Possibly, with some investment in appropriate hardware. Please do your own research before you make your own decisions.

Knowing that some currencies like Monero can be mined with CPU based mining scripts alone, I wondered what it would look like to package a miner as a Docker image, and then run it at scale on a Kubernetes cluster. As you do, right?

First, I followed a Monero getting started guide to pull the source and build a suggested miner, then captured the steps to build the miner as a Dockerfile like this:

FROM ubuntu:17.10

#build steps from https://www.monero.how/tutorial-how-to-mine-monero
RUN apt-get update && apt-get install -y git libcurl4-openssl-dev \
 build-essential libjansson-dev autotools-dev automake
RUN git clone https://github.com/hyc/cpuminer-multi
RUN cd /cpuminer-multi && ./autogen.sh && ./configure && make
WORKDIR /cpuminer-multi
ENTRYPOINT ["./minerd"]

This Dockerfile contains the steps you’d follow to pull the source and build locally, but written to build a Docker image.

Next,  build and tag the image with the ip of your local Docker repo, ready for deploying to your Kubernetes cluster:

Build the image:

docker build -t monero-cpuminer .

Tag and push the image (192.168.1.80:5000 here is my local Docker Repository) :

docker tag monero-cpuminer 192.168.1.80:5000/monero-cpuminer
docker push 192.168.1.80:5000/monero-cpuminer

Before we start the deployment to Kubernetes, let’s check kubectl on my dev laptop can reach my Kubernetes cluster on my rack server:

kubectl get nodes --kubeconfig ~/kubernetes/admin.conf 

NAME                  STATUS    ROLES     AGE       VERSION

unknown000c2960f639   Ready     master    50d       v1.8.1

unknown000c297262c7   Ready     <none>    50d       v1.8.1

unknown000c29ab1af7   Ready     <none>    50d       v1.8.1

Nodes are up and ready to deploy.

Following the example .yml deployment file here, here’s my Kubernetes deployment file:

apiVersion: apps/v1beta2 # for versions before 1.8.0 use apps/v1beta1
kind: Deployment
metadata:
  name: monero-cpuminer-deployment
  labels:
    app: monero-cpuminer-deployment
spec:
  replicas: 2
  selector:
    matchLabels:
      app: monero-cpuminer-deployment
  template:
    metadata:
      labels:
        app: monero-cpuminer-deployment
    spec:
      containers:
      - name: monero-cpuminer-deployment
        image: 192.168.1.80:5000/monero-cpuminer
        args: [ "-o", "stratum+tcp://monerohash.com:3333", "-u", "your-wallet-id" ]

The args passed to the container are (scroll to the right above):

args: [ “-o”, “stratum+tcp://monerohash.com:3333”, “-u”, “your-wallet-id” ]

I’m using the monerohash.com mining pool – you can checkout their settings here.

Now let’s deploy with:

kubectl apply -f cpuminer-deployment.yml --kubeconfig ~/kubernetes/admin.conf

Listing the pods we can now see the two we requested starting up:

kubectl get pods --kubeconfig ~/kubernetes/admin.conf 

And we can check the status and other info about the deployment config with:

kubectl describe deployments monero-cpuminer-deployment --kubeconfig ~/kubernetes/admin2.conf 

This shows my required replicas available:

Replicas:               2 desired | 2 updated | 2 total | 2 available | 0 unavailable

Now let’s scale it up to 4 replicas:

$ kubectl scale --replicas=4 deployment/monero-cpuminer-deployment --kubeconfig ~/kubernetes/admin2.conf 

deployment "monero-cpuminer-deployment" scaled

Replicas:               4 desired | 4 updated | 4 total | 4 available | 0 unavailable

Scaling up from 2 pods, to 4, then 8, we’re at about 75% of available CPU in my 2x Xeon HP DL380 rack server:

Fan speeds have ramped up from idle, but still comfortably running:

Hash rate so far:

So is it possible to run a Monero miner in Docker containers? Sure! Can you deploy to a kubernetes cluster and scale it up? Sure! Is it worthwhile? Probably not, and probably not profitable, unless you’ve got some spare low power consuming hardware handy, or something custom built to provide a cost effective hash rate depending on your power consumption and local utility rates. Still, personally this was an interesting exercise to check out building a Monero miner from source, and how to package it as a Docker image and deploy to Kubernetes.

Leave me a comment if you’ve done something similar and what hash rates did you get?