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+FROM debian:bookworm-slim
+
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends \
+        python3 \
+        krb5-user \
+        dnsutils \
+        ca-certificates && \
+    rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+COPY dns_sync.py .
+COPY krb5.conf /etc/krb5.conf
+RUN chmod +x dns_sync.py
+
+USER nobody
+ENTRYPOINT ["python3", "/app/dns_sync.py"]