Here’s a breakdown of what you need to know:
1. Use official images whenever possible This ensures that the image has been thoroughly tested and vetted by the community, reducing the risk of vulnerabilities or malicious code being introduced into your containers. 2. Keep your images up-to-date with security patches Regularly updating your images to include the latest security patches can help prevent known vulnerabilities from being exploited in your container environment. 3. Use non-root users for running processes inside the container This helps reduce the risk of a compromised container gaining access to sensitive system resources or data. 4. Limit network exposure by using host networking only when necessary By default, containers are isolated from each other and the host machine’s network stack. However, if you need to expose certain ports for testing purposes, be sure to use host networking instead of exposing them directly to the internet. 5. Use a container registry with strong security measures in place This can help prevent unauthorized access or tampering with your images before they are deployed to production environments. As for avoiding Docker’s default behavior of running as root, you can do this by creating a new user inside the container and setting its UID to match that of the host machine’s user ID. This allows you to run processes in the container without having to use sudo or elevated privileges. Here’s an example command for doing so:
# Create a new group called "mygroup" with a system account
groupadd -r mygroup
# Create a new user called "myuser" with a home directory and a user ID of 1000
useradd -m -u 1000 -g mygroup myuser
This creates a new group called “mygroup” with ID 1000, and adds a new user named “myuser” to that group. The UID of the user is set to 1000 (which matches the host machine’s default UID for non-root users), ensuring that processes run by this user inside the container have the same privileges as those running on the host machine.
Remember, always keep your images up-to-date with security patches and use non-root users whenever possible for added protection against potential attacks or vulnerabilities.