Docker Certification (How it Works for Developers)

What is Docker?

Docker is a free, open-source containerization, hence making it easier to develop, deploy, and maintain applications. It really is just a little thin, the light thing that actually contains an application with everything that an application depends on; it needs to work in as many contexts as feasible-from the developer's own computer to the production server. These containers are significantly more efficient and faster because they share the operating system kernel of the host system, unlike standard virtual machines.

Docker engine is only one of several companies that offer different models to generate, manage, and share those containers. A version of this model has even been named Docker images. The special type of Docker repository for sharing and storing container images is Docker Hub. One of the main reasons Docker technologies sees so much in cloud-based development workflows and DevOps is its supremacy in scalability, portability, and efficiency. Docker comes with two versions personal and docker enterprise edition.

What is a Docker certificate?

A Docker certificate is a digital certificate used to create secure communication between a Docker client and a Docker server, like a Docker daemon or Docker registry, through HTTPS. It is an important aspect of Docker's TLS configuration, which allows only clients and servers to interact with each other. It is quite useful when one deploys Docker in production or distributed environments.

Features of Docker Certificates

TLS/SSL Authentication: It applies TLS/SSL certificates to authenticate clients and servers to ensure that they come from legitimate sources.

Encryption: Docker enables encrypted data transmission between client and server sides through certificates. These certificates are not readable to others.

Mutual Authentication: Mutual TLS implements mutual authentication of certificates between client and server. It provides absolute security because verifying either party's certificate must precede any data transfer.

Types of Certificates in Docker

Server Certificate: It allows the client to authenticate the Docker daemon. The server Certificate is installed on the server running Docker.

Client Certificate: it is issued to the Docker client that issued it for authentication on a server. The Client Certificate will have to be signed based on a trusted CA.

CA Certificate: This should be the CA Certificate on both parties used to sign either the server or client certificate and create trusted relations between the two parties.

Using a Custom Certificate Authority (CA)

If we are running a custom CA, we will need to make Docker trust this CA. We would normally be configuring Docker to point at your CA by storing the CA certificate in /etc/docker/certs.d//ca.crt on your Docker host.

We should paste our CA certificate in /etc/docker/certs.d//ca.crt on your Docker host.

Using Docker with TLS

The Docker daemon itself can be protected by TLS by generating server and client certificates and then configuring Docker to use them in communications.

Generate Certificates

Use OpenSSL to generate the required certificates:

openssl genrsa -aes256 -out ca-key.pem 4096
openssl req -new -x509 -days 365 -key ca-key.pem -sha256 -out ca.pem

openssl genrsa -aes256 -out ca-key.pem 4096
openssl req -new -x509 -days 365 -key ca-key.pem -sha256 -out ca.pem

'INSTANT VB TODO TASK: The following line uses invalid syntax:
'openssl genrsa -aes256 -out ca-key.pem 4096 openssl req -New -x509 -days 365 -key ca-key.pem -sha256 -out ca.pem

Create client and server keys and certificates now:

openssl genrsa -out server-key.pem 4096
openssl req -subj "/CN=your-server" -sha256 -new -key server-key.pem -out server.csr
openssl x509 -req -days 365 -sha256 -in server.csr -CA ca.pem -CAkey ca-key.pem -CAcreateserial -out server-cert.pem

openssl genrsa -out server-key.pem 4096
openssl req -subj "/CN=your-server" -sha256 -new -key server-key.pem -out server.csr
openssl x509 -req -days 365 -sha256 -in server.csr -CA ca.pem -CAkey ca-key.pem -CAcreateserial -out server-cert.pem

'INSTANT VB TODO TASK: The following line uses invalid syntax:
'openssl genrsa -out server-key.pem 4096 openssl req -subj "/CN=your-server" -sha256 -New -key server-key.pem -out server.csr openssl x509 -req -days 365 -sha256 -in server.csr -CA ca.pem -CAkey ca-key.pem -CAcreateserial -out server-cert.pem

Finally, configure Docker to utilize these certificates: put them in the right directories and correct the Docker daemon configuration

Configure Docker Daemon

To utilize the generated certificates, change the Docker daemon's configuration:

{
  "tls": true,
  "tlsverify": true,
  "tlscacert": "/etc/docker/ca.pem",
  "tlscert": "/etc/docker/server-cert.pem",
  "tlskey": "/etc/docker/server-key.pem",
  "hosts": ["tcp://0.0.0.0:2376", "unix:///var/run/docker.sock"]
}

{
  "tls": true,
  "tlsverify": true,
  "tlscacert": "/etc/docker/ca.pem",
  "tlscert": "/etc/docker/server-cert.pem",
  "tlskey": "/etc/docker/server-key.pem",
  "hosts": ["tcp://0.0.0.0:2376", "unix:///var/run/docker.sock"]
}

If True Then
  "tls": True, "tlsverify": True, "tlscacert": "/etc/docker/ca.pem", "tlscert": "/etc/docker/server-cert.pem", "tlskey": "/etc/docker/server-key.pem", "hosts": ("tcp://0.0.0.0:2376", "unix:///var/run/docker.sock")
End If

Restart the Docker daemon to apply the changes.

Docker certification Exam

Docker Certified Associate is a globally recognized certification aimed at authenticating a candidate's expertise in Docker skills. Docker certifications contain around 55 multiple-choice and multiple-select type questions in nature that are asked in this online proctored exam (Docker certified associate certification), which should be solved within 90 minutes.

It includes six major domains orchestration, creation and management of images, installation and configuration, networking, security, and storage. While there are no strict prerequisites, the candidates are encouraged to have at least six months of practical experience in using Docker and should have a good level of understanding of how things work in containerized application workflows, docker certification valid for two years.

Prep includes studying Docker documentation, practicing CLI commands, working with Docker Swarm and Docker Compose, and using mock exams. Acquiring the DCA means one demonstrates proficiency in Docker and gives one better career prospects within DevOps, cloud-native development, and container orchestration. To learn more about the Docker training course, check here.

What is IronSecureDoc?

IronSecureDoc is a recently developed product by Iron Software that is specially designed with the aim of securing documents digitally, especially PDFs with quite robust encryption and controls in place. This will further allow an organization to install advanced encryption protocols like AES-256 so that the said sensitive information cannot be viewed without authorized permission. The company has custom permissions and restrictions on printing, editing, or copying, meaning that the document can only be opened by an authorized user. Password protection, as well as digital signatures, also increase the security and integrity of documents and watermarking.

IronSecureDoc is developer-friendly and can easily accommodate applications through Docker or other programming environments, so it should be able to adapt to many business workflows. For instance, in the health, finance, and legal industries, confidentiality of documents means everything. IronSecureDoc will combine the features of encryption and control of the documents within an organization and ensure their safekeeping to allow compliance and easy, safe sharing with a partner or client outside.

How Certificates Enhance IronSecureDoc Security

Authentication: The certificates are such that user or system authentication is possible on the secured document, and it's only the authorized person who will access the file. This is very fundamental to compliance and internal security especially where regulated industries have their participation such as in finance and healthcare.

Encryption: In public key encryption, files can be encrypted by IronSecureDoc such that a file encrypted with it can be opened only by an individual having the corresponding private key. Therefore, no matter how hard it might try, intercepted content cannot be accessed.

Digital Signatures: Certificates allow digital signing, which gives origin and integrity to the document. A valid signature assures that the document has not changed, thus ensuring more trust and fulfilling legal criteria for digital transactions.

Install and Running IronsecureDoc

Run the following command at the Command Prompt or in an open terminal window to pull the IronSecureDoc Docker image from the repository.

docker pull ironsoftwareofficial/ironsecuredoc

docker pull ironsoftwareofficial/ironsecuredoc

After pulling an image from the Docker container, we can employ another command to start the IronSecureDoc, an operating container.

docker container run --rm -p 8080:8080 -e IronSecureDoc_LicenseKey=<IRONSECUREDOC_LICENSE_KEY> -e ENVIRONMENT=Development -e HTTP_PORTS=8080 ironsoftwareofficial/ironsecuredoc:latest

docker container run --rm -p 8080:8080 -e IronSecureDoc_LicenseKey=<IRONSECUREDOC_LICENSE_KEY> -e ENVIRONMENT=Development -e HTTP_PORTS=8080 ironsoftwareofficial/ironsecuredoc:latest

The above Docker run command will create a container instance of the IronSecureDoc.

Using IronSecuredoc

IronSecureDoc's REST API lets the users redact, certify, and encrypt documents right at installation and launch in Docker; it has also been mentioned elsewhere. Here is the link to the documentation.

For instance, to encrypt a document, you can POST to the IronSecureDoc API:

curl -X 'POST' \
  'http://localhost:8080/v1/document-services/pdfs/encrypt?user_password=demo' \
  -H 'accept: */*' \
  -H 'Content-Type: multipart/form-data' \
  -F 'pdf_file=@test.pdf;type=application/pdf'

curl -X 'POST' \
  'http://localhost:8080/v1/document-services/pdfs/encrypt?user_password=demo' \
  -H 'accept: */*' \
  -H 'Content-Type: multipart/form-data' \
  -F 'pdf_file=@test.pdf;type=application/pdf'

This will automatically forward the document to IronSecureDoc, where it will be appropriately encrypted.

Conclusion

The Docker certificates and IronSecureDoc thus form a comprehensive, secure framework for managing documents in containerized environments. The Docker certificates facilitate encrypted and authenticated communication between Docker clients and servers to ensure the secure deployment and management of container hosting applications like IronSecureDoc. Only trusted entities will have access to and modify Docker containers, thus preventing any unauthorized actions within the server environment.

This is supported by IronSecureDoc, in which document-specific security features can be added such as file encryption, implementing access controls, and authentication of the authenticity of the document through digital signatures. Together with Docker certificates and IronSecureDoc, complete security-protecting of both the infrastructure and stored sensitive data is delivered. For more information about licensing Ironsecuredoc, click on this page. For information about many of the products from Iron Software, follow this link.