Dockerfile

# syntax=docker/dockerfile:1

FROM debian:trixie-slim

ARG TARGETARCH
ARG VERSION_ARG="4.2.0"

ARG DEBCONF_NOWARNINGS="yes"
ARG DEBIAN_FRONTEND="noninteractive"
ARG DEBCONF_NONINTERACTIVE_SEEN="true"

SHELL ["/bin/bash", "-c"]

RUN <<EOF

# Break on errors
set -Eeuo pipefail

# Install prerequisites
apt-get update
apt-get install -y --no-install-recommends \
  bc \
  jq \
  curl \
  tini \
  nano \
  wget \
  htop \
  less \
  cpio \
  dpkg \
  gosu \
  iotop \
  gnupg \
  procps \
  locales \
  rsyslog \
  postfix \
  iptables \
  iproute2 \
  ifupdown2 \
  jfsutils \
  xfsprogs \
  e2fsprogs \
  net-tools \
  nfs-common \
  cifs-utils \
  traceroute \
  open-iscsi \
  btrfs-progs \
  iputils-ping \
  netcat-openbsd \
  ca-certificates \
  isc-dhcp-client

# Prevent services from starting during install
printf '#!/bin/sh\nexit 101\n' > /usr/sbin/policy-rc.d
chmod +x /usr/sbin/policy-rc.d

# Block unneeded packages in container
cat >/etc/apt/preferences.d/99-pdm-unneeded-packages <<BLK
Package: proxmox-default-kernel proxmox-kernel-* pve-firmware
Pin: release *
Pin-Priority: -1
BLK

# Stub commands unavailable / problematic in a Docker build
dpkg-divert --local --rename --add /usr/bin/unshare
printf '#!/bin/sh\nwhile [ $# -gt 0 ] && [ "$1" != "--" ]; do shift; done\n[ "$1" = "--" ] && \
shift\n[ $# -gt 0 ] && exec "$@"\nexit 0\n' > /usr/bin/unshare
chmod +x /usr/bin/unshare
dpkg-divert --local --rename --add /usr/sbin/update-initramfs
printf '#!/bin/sh\nexit 0\n' > /usr/sbin/update-initramfs
chmod +x /usr/sbin/update-initramfs
dpkg-divert --local --rename --add /usr/sbin/ifreload
printf '#!/bin/sh\n[ "$1" = "-V" ] && printf "%%s\n" "ifupdown2:3.3.0-1+pmx12"\nexit 0\n' > /usr/sbin/ifreload
chmod +x /usr/sbin/ifreload
printf '#!/bin/sh\nexit 0\n' > /usr/local/sbin/systemctl
chmod +x /usr/local/sbin/systemctl

# Install Proxmox Backup Server

if [[ "$TARGETARCH" == "amd64" ]]; then

  # Add Proxmox Backup Server repository
  curl -sL https://enterprise.proxmox.com/debian/proxmox-archive-keyring-trixie.gpg \
       -o /usr/share/keyrings/proxmox-archive-keyring.gpg

  cat <<'DEB' | sed 's/^[[:space:]]*//' > /etc/apt/sources.list.d/pbs-no-subscription.sources
    Types: deb
    URIs: http://download.proxmox.com/debian/pbs
    Suites: trixie
    Components: pbs-no-subscription
    Signed-By: /usr/share/keyrings/proxmox-archive-keyring.gpg
DEB

  apt-get update
  apt-get install -y --no-install-recommends \
    proxmox-backup-docs \
    proxmox-backup-client \
    proxmox-backup-server

else

  apt-get install -y --no-install-recommends \
    git \
    sudo \
    dpkg-dev \
    apt-transport-https

  tmpdir="/tmp/deb"
  rm -rf "$tmpdir"
  mkdir -p "$tmpdir"

  # Download packages from repo: qemus/proxmox-backup-arm64
  git clone --depth 1 https://github.com/qemus/proxmox-backup-arm64.git "$tmpdir"
  chmod +x "$tmpdir/build.sh"

  (cd "$tmpdir" && ./build.sh "install=${VERSION_ARG}")
  rm -rf "$tmpdir"

  SUDO_FORCE_REMOVE=yes apt-get remove -y \
    git \
    sudo \
    dpkg-dev \
    apt-transport-https

fi

# Prevent system updates
apt-mark hold \
   proxmox-backup-docs \
   proxmox-backup-client \
   proxmox-backup-server

# Install supercronic
if [[ "$TARGETARCH" == "amd64" ]]; then

  SUPERCRONIC=supercronic-linux-amd64
  SUPERCRONIC_URL=https://github.com/aptible/supercronic/releases/download/v0.2.46/supercronic-linux-amd64

else

  SUPERCRONIC=supercronic-linux-arm64
  SUPERCRONIC_URL=https://github.com/aptible/supercronic/releases/download/v0.2.46/supercronic-linux-arm64

fi

curl -fsSLO "$SUPERCRONIC_URL"
chmod +x "$SUPERCRONIC"
mv "$SUPERCRONIC" "/usr/local/bin/${SUPERCRONIC}"
ln -s "/usr/local/bin/${SUPERCRONIC}" /usr/local/bin/supercronic

# Remove enterprise repo added by Proxmox packages — keep only no-subscription
rm -f /etc/apt/sources.list.d/pbs-enterprise.list \
      /etc/apt/sources.list.d/pbs-enterprise.sources \
      /etc/apt/sources.list.d/ceph.list \
      /etc/apt/sources.list.d/ceph.sources

# Cleanup
apt-get autoremove -y
apt-get clean

# Generate locales
locale-gen en_US.UTF-8

# Set username and password
echo "root:root" | chpasswd

# Redirect rsyslog
sed -i '/.*imklog.*/d' /etc/rsyslog.conf && \
    echo '*.* -/proc/1/fd/1' >> /etc/rsyslog.conf

# Store version number
echo "$VERSION_ARG" > /etc/version

# Remove stub
rm /usr/local/sbin/systemctl

# Cleanup files
rm -rf /tmp/* /var/tmp/* /var/lib/apt/lists/*

EOF

WORKDIR /usr/local/bin
COPY --chmod=755 ./src /usr/local/bin/

ENV PASSWORD="root"

EXPOSE 8007

VOLUME /etc/proxmox-backup
VOLUME /var/lib/proxmox-backup

HEALTHCHECK --interval=60s --timeout=10s --start-period=60s --retries=3 \
    CMD ["curl", "-kLfSs", "https://localhost:8007/"]

ENTRYPOINT ["/usr/bin/tini", "-s", "/usr/local/bin/entrypoint.sh"]