To check a file Docker Composing, start with docker compose config. Then check network exposure, privileges, secrets, volumes, image versions, healthchecks and resources. The valid syntax does not guarantee the security or reliability of deployment.
Validate Compose before the checklist
ConfigCheck analyzes the file and the Dockerassociated files without running image. It completes the local control with security and reliability checks.
Validate my Compose fileExhibition and privileges
1. Publish all ports on all interfaces
When only the local proxy reverse must join the service, link the port to 127.0.0.1 rather than all interfaces. Also check that internal ports between services are not unnecessarily published on the host.
2. Use privileged: true
This mode greatly expands the rights of the container. Prefer specific capabilities, remove unnecessary ones and activate no-new-privileges.
3. Mount socket Docker
Access to /var/run/docker.sock usually allows a very important host control. Avoid it or interpose a strictly limited mechanism.
Secrets and data
4. Write a secret directly in Compose
A committed password remains in history. Use a suitable secret mechanism or a protected, unedited environment file limited to the required accounts.
5. Mount a host directory too wide
Prefer an explicit path and read-only mode when writing is not necessary. Also check the owner and host directory permissions.
Reliability
6. Use only latest
A redeployment can then recover a different content. Fig a version or digest and schedule updates.
7. Consolidate start-up and availability
depends_on does not always prove that the application is ready. Add a health control that checks for useful behavior and a consistent recovery strategy.
8. Forget the limits
A memory leak or loop may affect other services. Set limits consistent with load measurements and observe their effect before production.
9. Let go of root
Combine a non-privileged user in the image, a read-only file system and a limited temporary directory.
10. Do not organize newspapers
Limit the size and rotation to avoid saturating the disc while maintaining enough history to diagnose.
A three-level validation
- Structure: Run
docker compose config -qand check the references between services, networks and volumes. - Security: Examine sensitive ports, secrets, privileges, capabilities and mounts.
- Operation: control versions, healthchecks, resources, logs and restart conditions.
Use it Docker Compose validator online To obtain a first static analysis, then test the project in an isolated environment.
Frequently Asked Questions
How to check a file Docker Compose before deployment?
Validate configuration, then control ports, volumes, secrets, privileges, image versions, healthchecks and resource limits.
Why Avoid privileged: true ?
This mode gives the container very extensive rights. Add only the really necessary capabilities.
Should I use latest for images Docker ?
Avoid it for repeatable deployments. Use a controlled version or digest and schedule updates.
Does a healthcheck guarantee that the application works?
Only if the test checks for useful behavior. Starting the process is not enough to prove that the service is available.
Published on 19 July 2026, updated on 20 August 2026.