Simple Nginx Conf for Microservices Application

########################################################################

# Main Nginx configuration file for Dockerized Microservices

#

# More information about the configuration options is available on 

# * the English wiki - http://wiki.nginx.org/Main

# * the Russian documentation - http://sysoev.ru/nginx/

#

#######################################################################

#----------------------------------------------------------------------

# Main Module - directives that cover basic functionality

#

# http://wiki.nginx.org/NginxHttpMainModule

#

#----------------------------------------------------------------------

user nginx;

worker_processes auto;

error_log /opt/nginx/logs/error.log;

#error_log /var/log/nginx/error.log notice;

#error_log /var/log/nginx/error.log info;

pid /var/run/nginx.pid;

#----------------------------------------------------------------------

# Events Module 

#

# http://wiki.nginx.org/NginxHttpEventsModule

#

#----------------------------------------------------------------------

events {

    worker_connections 2048;

}

#----------------------------------------------------------------------

# HTTP Core Module

#

# http://wiki.nginx.org/NginxHttpCoreModule 

#

#----------------------------------------------------------------------

http {

    include /opt/nginx/conf/mime.types;

    default_type application/octet-stream;

    log_format main '$remote_addr - $remote_user [$time_local] "$request" '

                      '$status $body_bytes_sent "$http_referer" '

                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log /opt/nginx/logs/access.log main;

    sendfile on;

    autoindex off;

    

    map $scheme $fastcgi_https {

        default off;

        https on;

    }

    keepalive_timeout 60;

    gzip on;

    gzip_comp_level 2;

    gzip_proxied any;

    gzip_types text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript;

    gzip_disable "msie6";

    gzip_vary on;

    gzip_min_length 1024;

    gzip_http_version 1.1;

    # gzip_static on;

    # Load config files from the /etc/nginx/conf.d directory

    # The default server is in conf.d/default.conf

    include /opt/nginx/conf/conf.d/*.conf;

    # include /etc/nginx/sites-enabled/*;

    # tcp_nopush on;

}

How to Start with OpenStack

 

                                                                            Photo by Karolina Grabowska

OpenStack is a powerful open-source cloud computing platform that provides a range of features and benefits, making it a popular choice for organizations looking to build and manage their own cloud infrastructure. Here are some key features and reasons why you might consider using OpenStack:

1. Open-Source and Vendor-Neutral: OpenStack is open-source, which means it's freely available and not tied to any particular vendor. You have the flexibility to customize and extend it to meet your specific needs.

2. Scalability: OpenStack is designed to scale, making it suitable for small to large cloud deployments. You can add more compute, storage, and network resources as your needs grow.

3. Modular Architecture: OpenStack follows a modular architecture, which means you can choose to deploy only the components you need. Common modules include Compute (Nova), Networking (Neutron), Storage (Cinder and Swift), Identity (Keystone), and more.

4. Multi-Tenancy: OpenStack supports multi-tenancy, enabling you to create isolated environments for different users, teams, or customers on a shared infrastructure.

5. API Compatibility: OpenStack offers RESTful APIs for managing and provisioning cloud resources. This makes it easier to integrate with other tools, applications, and services.

6. Orchestration: OpenStack provides orchestration capabilities through services like Heat. You can automate complex workflows and application deployments.

7. Infrastructure as a Service (IaaS): OpenStack primarily serves as an IaaS platform, allowing you to create virtualized infrastructure resources, including virtual machines, storage, and networks.

8. Heterogeneous Hardware Support: OpenStack can work with various types of hardware, allowing you to use existing infrastructure and gradually upgrade or replace components as needed.

9. Community and Ecosystem: OpenStack has a large and active community of developers and users, which means you can benefit from their collective knowledge, expertise, and contributions.

10. Private and Hybrid Clouds: OpenStack is well-suited for building private clouds within your data center. You can also integrate with public cloud services, like AWS, Azure, or Google Cloud, to create a hybrid cloud environment.

11. Security: OpenStack has built-in security features, and its modular design allows you to customize and strengthen security based on your specific requirements.

12. Customization: OpenStack's open-source nature allows for extensive customization. You can tailor your cloud environment to meet your unique business needs.

13. Backup and Disaster Recovery: OpenStack provides backup and disaster recovery features to protect your data and applications from unexpected failures or disasters.

14. Object Storage: OpenStack Swift offers a scalable and redundant object storage system, ideal for storing unstructured data and media files.

15. Image Management: OpenStack Glance allows you to manage and store virtual machine images, making it easy to create and deploy virtual machines.

16. Network Virtualization: OpenStack Neutron provides powerful networking features, including software-defined networking (SDN), load balancing, and firewall services.

17. Analytics and Monitoring: OpenStack supports integration with monitoring and analytics tools, helping you keep track of your cloud's performance and usage.

18. Machine Learning and AI: OpenStack can be used as a foundation for deploying machine learning and AI workloads in a cloud environment.

19. Community and Support: There's a wealth of community-driven documentation, resources, and forums to assist with OpenStack deployments. Additionally, commercial vendors offer professional support for OpenStack.

OpenStack's rich feature set and flexibility make it a compelling choice for organizations that need control over their cloud infrastructure and want to build private, public, or hybrid clouds to meet their specific business requirements.

Learning and setting up OpenStack for the first time can be a complex task, but with your experience in software development and related technologies, you have a good foundation to get started. Here's an end-to-end guide to help you set up OpenStack and integrate it with Azure for your application.

1. Understanding OpenStack:

Before diving into setup, it's essential to understand what OpenStack is. OpenStack is an open-source cloud computing platform that allows you to create and manage both public and private clouds. It provides various cloud services, including compute, storage, networking, and more.

2. Environment Requirements:

You'll need a set of hardware and software for your OpenStack deployment:

- Physical or virtual servers for hosting OpenStack components (compute, controller, network, and storage nodes).

- Linux-based operating system (Ubuntu, CentOS, etc.).

- Sufficient RAM, CPU, and disk space.

- Familiarity with virtualization technologies (e.g., KVM).

- Access to the internet for package installation and updates.

3. Setting Up OpenStack:

Here's a high-level overview of the steps to set up OpenStack:

    a. Install and Configure the Operating System:

- Install your chosen Linux distribution on the hardware you've selected for OpenStack.

    b. Deploy OpenStack Services:

OpenStack is composed of several services. You'll typically need the following core services:

- Nova (Compute)

- Neutron (Networking)

- Cinder (Block Storage)

- Keystone (Identity)

- Glance (Image Service)

- Horizon (Dashboard)

Each of these services requires its own configuration. The [OpenStack documentation](https://docs.openstack.org/) is a valuable resource for detailed instructions.

    c. Networking Configuration:

- Configure your network settings and ensure that network connectivity is working as expected.

- Neutron will help manage networking services in OpenStack.

    d. Identity and Authentication:

- Set up Keystone to manage user accounts and authentication.

- Define roles and permissions for your users.

    e. Compute and Storage:

- Configure Nova for managing your virtual machines.

- Set up Cinder for block storage.

- Integrate Glance for managing virtual machine images.

    f. Web Dashboard:

- Install and configure Horizon for a web-based dashboard to manage your OpenStack environment.

    g. Azure Integration:

To integrate with Azure as a public cloud, you can use tools like Azure Stack. Azure Stack allows you to extend Azure services and capabilities to your on-premises or edge environments.

    4. Python-Based Application:

Now that your OpenStack environment is set up, you can develop your Python-based application. Ensure your application uses OpenStack's APIs to provision and manage cloud resources.

    5. Deploying on ARM and Web Stack:

- For deploying your application on ARM devices like Raspberry Pi and Toradex, you need to cross-compile your application for the respective architecture.

- For web stacks, ensure that your application is web-ready and can be hosted on web servers like Apache or Nginx.

    6. Testing:

- Thoroughly test your application in your OpenStack environment and on ARM and web stacks.

- Ensure that your integration with Azure is functioning correctly.

    7. Scaling and Maintenance:

As your application grows, you may need to scale your OpenStack deployment. Regular maintenance and updates are crucial for the security and performance of your cloud.

    8. Documentation and Monitoring:

Document your setup and configurations. Implement monitoring and logging to keep an eye on your environment and application.

OpenStack deployment is a complex process, and this is just an overview. You should refer to the official OpenStack documentation and Azure documentation for detailed setup and integration instructions. Additionally, consider using automation tools like Ansible and Terraform to streamline your deployment process.

If your application relies on several Docker containers and you want to manage these containers in an OpenStack-based cloud environment, you'll need to follow some specific steps. Below is an overview of how you can set up OpenStack to work with Docker containers:

Prerequisites:

1. OpenStack Cloud: You should have an OpenStack cloud environment up and running. If not, refer to the previous discussion on setting up OpenStack.

2. Docker: Ensure you have Docker installed on the virtual machines where you plan to run your containers.

3. Linux OS: Make sure you are using a Linux distribution that supports Docker and OpenStack. Ubuntu and CentOS are popular choices.

Steps to Deploy Docker Containers in OpenStack:

1. Set Up OpenStack Flavors and Images:

   - In your OpenStack dashboard (Horizon), define flavors that represent different configurations for your virtual machines. For example, you can create flavors with varying CPU, memory, and disk configurations.

   - Prepare a base image for your virtual machines with Docker installed. You can use an official Linux distribution image or create a custom image with Docker pre-installed.

2. Create Security Groups:

   - Define security groups and rules to control network traffic between your containers and the external world. Ensure that you open ports for the services your containers provide.

3. Network Configuration:

   - Set up networking in OpenStack. Create private networks, routers, and subnets. You may want to use the OpenStack Neutron service to manage network resources.

4. Orchestration with Heat (Optional):

   - If you have complex setups with multiple containers that need to work together, consider using OpenStack Heat for orchestration. Create Heat templates to describe your entire stack, including virtual machines and their Docker containers.

5. Nova Instances (VMs) Creation:

   - Launch Nova instances (virtual machines) based on your flavors and images. These instances will serve as hosts for your Docker containers.

6. Docker Containers Deployment:

   - SSH into your Nova instances.

   - Install Docker on these instances if not pre-installed.

   - Use Docker Compose or other container orchestration tools like Kubernetes to define your application's container setup.

   - Pull Docker images from a registry (e.g., Docker Hub) or push your custom images to an image registry within your OpenStack environment.

7. Start Docker Containers:

   - Start Docker containers on your Nova instances. Ensure that they are properly networked and can access any required external services or resources.

8. Monitoring and Scaling:

   - Implement monitoring and scaling solutions as needed. Tools like Prometheus, Grafana, and Docker Swarm or Kubernetes can be useful for this purpose.

9. Backup and Disaster Recovery:

   - Implement backup and disaster recovery solutions for your Docker containers. Docker provides features like volume management for data persistence.

10. Security:

    - Implement proper security practices for your containers, including container runtime security, user access controls, and regular security updates.

11. Integration with Other Services:

    - If your application relies on databases, caches, message queues, or other services, ensure that they are set up and integrated correctly within your OpenStack environment.

12. Testing and Optimization:

    - Thoroughly test your application and its containers in the OpenStack environment. Optimize your setup for performance and reliability.

13. Documentation:

    - Document your deployment and configuration procedures, as well as any custom scripts or tools used in the process.

14. Automation and Scaling:

    - Consider using automation tools like Ansible or Terraform to automate the deployment and scaling of your Docker containers in OpenStack.

Once you have set up your Docker containers within OpenStack, you can easily manage and scale your application as needed while benefiting from the flexibility and control that OpenStack provides.

Remember that the specific details of your implementation will depend on your application's requirements and the OpenStack components you are using. Make sure to consult the OpenStack documentation and Docker documentation for detailed information on configuration and best practices.

You can read my other articles for Kubernetes. 

Run Two Systemd Services Alternately

To achieve the desired sequence where `app1` starts, runs for 10 minutes, then `app2` starts and runs for 10 minutes, and this cycle repeats, you can create two separate timer units and services, one for each application, and use a cyclic approach. Here's how you can do it:

1. Create two timer units, one for each application, with cyclic activation:

   `myapp1.timer`:

   ```ini

   [Unit]

   Description=Timer for My Application 1

   [Timer]

   OnBootSec=10min

   OnUnitInactiveSec=10min

   [Install]

   WantedBy=timers.target

   ```

   `myapp2.timer`:

   ```ini

   [Unit]

   Description=Timer for My Application 2

   [Timer]

   OnBootSec=20min

   OnUnitInactiveSec=10min

   [Install]

   WantedBy=timers.target

   ```

In this configuration, `myapp1.timer` is set to trigger `myapp1.service` 10 minutes after boot and every 10 minutes after it becomes inactive. `myapp2.timer` is set to trigger `myapp2.service` 20 minutes after boot and every 10 minutes after it becomes inactive.

2. Create two service units, one for each application:

   `myapp1.service`:

   ```ini

   [Unit]

   Description=My Application 1

   [Service]

   ExecStart=/path/to/app1

   Restart=always

   [Install]

   WantedBy=multi-user.target

   ```

   `myapp2.service`:

   ```ini

   [Unit]

   Description=My Application 2

   [Service]

   ExecStart=/path/to/app2

   Restart=always

   [Install]

   WantedBy=multi-user.target

   ```

Replace `/path/to/app1` and `/path/to/app2` with the actual paths to your application executables.

3. Enable and start both timer units:

   ```

   sudo systemctl enable myapp1.timer

   sudo systemctl enable myapp2.timer

   sudo systemctl start myapp1.timer

   sudo systemctl start myapp2.timer

   ```

With this setup, `app1` will start when the system boots, run for 10 minutes, then stop. After that, `app2` will start and run for 10 minutes, and the cycle repeats. This pattern continues indefinitely.