Recover Lost Docker Run Commands in 3 Steps: runlike + composerize Guide

Problem Scenario: Undocumented Legacy MySQL Container

Many operations engineers inherit servers running Docker containers without documentation — unknown startup commands, missing configs, and departed colleagues. The article simulates a MySQL 8.0.35 container named prod-mysql-db deployed with a complex docker run command including:

Port mapping: -p 3306:3306 Volumes: /opt/mysql/data:/var/lib/mysql, /opt/mysql/conf:/etc/mysql/conf.d, /opt/mysql/init.sql:/docker-entrypoint-initdb.d/init.sql Environment variables: MYSQL_ROOT_PASSWORD, MYSQL_DATABASE=my_app_db, MYSQL_USER=app_user, MYSQL_PASSWORD Resource limits: --memory=2g --cpus=1.5 Restart policy: --restart=unless-stopped MySQL-specific flags:

--default-authentication-plugin=mysql_native_password --character-set-server=utf8mb4 --collation-server=utf8mb4_unicode_ci

Only the container name is known; the original command is lost.

Step 1: Reverse-Engineer the docker run Command with runlike

Installation Options

Option 1 (pip3):

# Install pip3 if missing
sudo yum install python3-pip
# Use Tsinghua mirror for speed
mkdir -p ~/.pip
echo -e "[global]
index-url = https://pypi.tuna.tsinghua.edu.cn/simple" > ~/.pip/pip.conf
pip3 install runlike

Option 2 (Docker image):

docker pull assaflavie/runlike:1.5.4

Generate the Command

# Via pip3 installation
runlike -p prod-mysql-db

# Via Docker image
docker run -v /var/run/docker.sock:/var/run/docker.sock assaflavie/runlike:1.5.4 prod-mysql-db

The tool outputs a complete docker run command reconstructing all original parameters:

docker run --name=prod-mysql-db \
  --hostname=727209fab8cc \
  --mac-address=02:42:ac:11:00:02 \
  --volume /opt/mysql/init.sql:/docker-entrypoint-initdb.d/init.sql \
  --volume /opt/mysql/conf:/etc/mysql/conf.d \
  --volume /opt/mysql/data:/var/lib/mysql \
  --env='MYSQL_ROOT_PASSWORD=SuperSecretRootPassword123!' \
  --env=MYSQL_DATABASE=my_app_db \
  --env=MYSQL_USER=app_user \
  --env='MYSQL_PASSWORD=UserPassword456!' \
  --network=bridge \
  -p 3306:3306 \
  --expose=33060 \
  --restart=unless-stopped \
  --runtime=runc \
  --memory="2147483648" \
  --detach=true \
  mysql:8.0.35 \
  --default-authentication-plugin=mysql_native_password --character-set-server=utf8mb4 --collation-server=utf8mb4_unicode_ci

All critical details — ports, volumes, env vars, restart policy, memory limit (2147483648 bytes = 2 GiB), and MySQL server arguments — are recovered.

Step 2: Convert to Docker Compose with composerize

Online Conversion (Recommended)

Visit https://www.composerize.com/, paste the generated docker run command, and the tool produces a docker-compose.yml.

Command-Line Conversion

# Install
npm install -g composerize

# Convert (paste the full run command)
composerize docker run --name=prod-mysql-db \
  --hostname=727209fab8cc \
  --mac-address=02:42:ac:11:00:02 \
  --volume /opt/mysql/init.sql:/docker-entrypoint-initdb.d/init.sql \
  --volume /opt/mysql/conf:/etc/mysql/conf.d \
  --volume /opt/mysql/data:/var/lib/mysql \
  --env='MYSQL_ROOT_PASSWORD=SuperSecretRootPassword123!' \
  --env=MYSQL_DATABASE=my_app_db \
  --env=MYSQL_USER=app_user \
  --env='MYSQL_PASSWORD=UserPassword456!' \
  --network=bridge \
  -p 3306:3306 \
  --expose=33060 \
  --restart=unless-stopped \
  --runtime=runc \
  --memory="2147483648" \
  --detach=true \
  mysql:8.0.35 \
  --default-authentication-plugin=mysql_native_password --character-set-server=utf8mb4 --collation-server=utf8mb4_unicode_ci

Resulting docker-compose.yml

services:
  mysql:
    container_name: prod-mysql-db
    hostname: 727209fab8cc
    mac_address: 02:42:ac:11:00:02
    volumes:
      - /opt/mysql/init.sql:/docker-entrypoint-initdb.d/init.sql
      - /opt/mysql/conf:/etc/mysql/conf.d
      - /opt/mysql/data:/var/lib/mysql
    environment:
      - MYSQL_ROOT_PASSWORD=SuperSecretRootPassword123!
      - MYSQL_DATABASE=my_app_db
      - MYSQL_USER=app_user
      - MYSQL_PASSWORD=UserPassword456!
    network_mode: bridge
    ports:
      - 3306:3306
    expose:
      - "33060"
    restart: unless-stopped
    runtime: runc
    deploy:
      resources:
        limits:
          memory: "2147483648"
    image: mysql:8.0.35
    command:
      --default-authentication-plugin=mysql_native_password
      --character-set-server=utf8mb4
      --collation-server=utf8mb4_unicode_ci

Step 3: Verify and Deploy

1. Stop Old Container (with Backup)

# Backup data first
mkdir -p /data/mysql-backup
docker cp prod-mysql-db:/var/lib/mysql /data/mysql-backup

# Stop and remove old container
docker stop prod-mysql-db
docker rm prod-mysql-db

2. Start with New Compose Configuration

cd /opt/mysql/
vim docker-compose.yml  # paste the generated content
docker-compose up -d

3. Validate Service Health

# Check container status
docker-compose ps

# View logs
docker-compose logs mysql

# Test database connection
docker exec -it prod-mysql-db mysql -h 127.0.0.1 -u root -p'SuperSecretRootPassword123!' -e "SHOW DATABASES;"

The verification confirms the migrated container runs identically with the recovered configuration.

Summary and Recommendations

The runlike + composerize combo solves the "lost Docker command" problem for any container, not just MySQL. The author advises operations teams to:

Regular Audits: Periodically check all running containers for documentation coverage.

Standardize First: Require Docker Compose or higher-level orchestration for new projects.

Document Everything: Store critical container configs in version control.

Security First: Use env files for secrets and enforce strict permissions.

Prevention beats cure — establishing standardized container management processes makes operations smoother and safer.

Tool References

runlike

:

https://github.com/lavie/runlike

composerize

:

https://www.composerize.com/