Docker Exit Code 125 - Docker Daemon Error

What It Means

Docker exit code 125 indicates that the Docker daemon itself encountered an error. The container’s process never started — the failure occurred at the Docker level before the application could run. This distinguishes it from exit code 1 (application error) and exit codes 126/127 (command issues).

Common Causes

• Invalid Docker run flags or options
• Port already in use (cannot bind)
• Volume mount path does not exist
• Insufficient permissions to access resources
• Invalid container configuration
• Image not found and cannot be pulled
• Docker daemon resource limits exceeded
• Invalid network configuration
• SELinux or AppArmor denying container operations

How to Fix

Check the error message

# Docker usually prints a descriptive error
docker run my-image
# Error response from daemon: ...

# Get more details with verbose output
docker --debug run my-image

Fix port conflicts

# Error: port is already allocated
docker run -p 3000:3000 my-image
# Error: bind: address already in use

# Find what's using the port
lsof -i :3000
# or
ss -tlnp | grep 3000

# Use a different host port
docker run -p 3001:3000 my-image

Fix volume mount issues

# Error: invalid mount path
docker run -v /nonexistent/path:/app/data my-image

# Ensure the host path exists
mkdir -p /path/to/data
docker run -v /path/to/data:/app/data my-image

# Fix permissions on mounted volumes
docker run -v /path/to/data:/app/data -u $(id -u):$(id -g) my-image

Fix image issues

# Error: image not found
docker run nonexistent-image:latest

# Pull the image first
docker pull my-image:latest

# Check if the image exists locally
docker images | grep my-image

# Try with full registry path
docker run registry.example.com/my-image:latest

Fix invalid flags

# Wrong: invalid flag combinations
docker run --network=host -p 3000:3000 my-image  # Can't use -p with host network

# Right: pick one network strategy
docker run --network=host my-image
# or
docker run -p 3000:3000 my-image

Fix Docker Compose issues

# Validate your docker-compose.yml
# docker compose config

services:
  app:
    image: my-image
    ports:
      - "3000:3000"
    volumes:
      - ./data:/app/data  # Ensure ./data exists
    environment:
      - NODE_ENV=production

Related Errors

• Docker Exit Code 1 - Application error: The container started but the app crashed.
• Docker Exit Code 126 - Command not executable: The entrypoint or CMD is not executable.
• Docker Exit Code 127 - Command not found: The entrypoint or CMD binary was not found.