This post is a short guide on hosting a privacy-focused comment system Remark42 on a virtual machine in the cloud for free or a small monthly fee.

Prague, Riegrovy sady, June 2022: photo by Ksenia Gulyaeva
Prague, Riegrovy sady, June 2022: photo by Ksenia Gulyaeva

Obtaining a virtual machine instance in the public cloud

Follow one of the instructions below to obtain an instance. At the end of the setup process, generate an SSH key and download it to your machine. The default location to store the private part of the key on Mac and Linux is ~/.ssh/id_rsa. You’ll need to connect to that instance using SSH during the next step.

Oracle Cloud, free

Register (requires credit card details) first. Then, create an instance there: you should pick a machine type Ampere “VM.Standard.A1.Flex” with 4 CPUs and 24GB of RAM. Initially, you would have a free trial for many resources, but that machine would be free and remain free for you for the time being.

In case you need more machines for other purposes, you can run up to four with 1 CPU and 6Gb of RAM each, as long as the total number of CPUs and RAM amount fits the number above. Oracle Linux is the default OS there, but you can pick something else like Ubuntu if you wish.

Digital Ocean, $4-$6 per month

Register first if you don’t have an account there yet. The link is a referral and would give you 100$ for 60 days, effectively giving free Remark42 hosting for the first two months.

Then, create the smallest\cheapest server possible in that cloud provider. For DigitalOcean, virtual machines are called droplets, and you need “Basic” -> “Regular with SSD” -> $4/month 1 CPU, 512MB RAM and 10GB SSD, or $6/month 1CPU, 1GB RAM and 20GB SSD if $4 option is not available in the region of your choice. Any operating system will do, in case you are unsure — pick Ubuntu.

How to start Remark42 on the virtual machine

  1. Before starting the work, point (with your domain name instead of to the IP address of the instance using your DNS provider.

  2. SSH to the instance and install Docker and docker-compose to it using this guide for Ubuntu or that for CentOS / Oracle Linux.

  3. Create docker-compose.yml on the instance and paste the content below into it:

    version: "2"
        image: umputun/remark42:latest
        container_name: "remark42"
        hostname: "remark42"
        restart: always
          driver: json-file
            max-size: "10m"
            max-file: "5"
          - "443:8443"
          # uncomment the line below to make remark42
          # work not only on HTTPS but also via HTTP
          # - "80:8080"
          - REMARK_URL=
          - SECRET=
          - DEBUG=true
          - SSL_TYPE=auto
          - AUTH_ANON=true
          # Enable it only for the initial comment
          # import or for manual backups.
          # Do not leave the server running with the
          # ADMIN_PASSWD set if you don't have an intention
          # to keep creating backups manually!
          # - ADMIN_PASSWD=<your secret password>
          - ./var:/srv/var

    Complete setup could be done using parameters’ documentation. Here are the minimum required steps:

    • set SECRET to a random string
    • set ADMIN_SHARED_EMAIL to your email address (Remark42 will subscribe it to HTTPS certificate renewal notifications)
    • replace with your domain name REMARK_URL
  4. Run docker compose up to start the instance and observe the logs. After that, (with your domain name instead of should show you the working Remark42 demo.

    After making sure that the Remark42 demo works, make it persistent. Stop the previous command by pushing Ctrl+C and run docker-compose up -d instead: it will run Remark42 in the background and start automatically on the VM restart. To see the log of the Remark42 container running in the background mode, you’ll need to run the command docker compose logs remark42 -f

After the steps above are done, you can set up the frontend according to the instruction.