DEV Community: Daniel Hu

Top 10 Open-Source DevOps Tools That You Should Know

Daniel Hu — Mon, 21 Nov 2022 03:42:37 +0000

Do you know how many open-source tools are in DevOps?

Have you ever seen the picture below?

Have you ever felt lost in the DevOps world with seemingly more than 1000 different tools?

If you are struggling with these questions now, then today you are in luck because I’m here to help you figure out the most popular DevOps tools.

Wait, what’s the DevOps?

"What's the DevOps?"

This's a controversial topic, and I'm not gonna go into it in this post. I'd like to give you an equation here only:

DevOps = Culture + Toolchain + Practice

And today I just want to introduce you to some popular tools.

If you are a Chinese reader, I can give you an article that I wrote some months ago which is named:

什么是 DevOps？看这一篇就够了！.

Top 10 Open-Source DevOps Tools Rundown

1、GitLab CE

GitLab Source Code Repository

There are 2 major editions of GitLab:

GitLab Community Edition (CE) is available freely under the MIT Expat license.
GitLab Enterprise Edition (EE) includes extra features that are more useful for organizations with more than 100 users.

Before I introduce you to GitLab, I'd like to talk a little bit about Git.
Git is a free and open-source distributed version control system designed to handle everything from small to very large projects with speed and efficiency.
Version control provides developers with a means by which they can keep track of all the changes and updates in their codes.
With Git, you must have thought that we need a "Git server". As an alternative to GitHub, if you want to deploy the "Git server" privately, GitLab CE might be a good choice.

GitLab CE is an open-source end-to-end software development platform with built-in version control, issue tracking, code review, CI/CD, etc.
The main features of GitLab CE are:

Manage Git repositories with fine-grained access controls that keep your code secure;
Perform code reviews and enhance collaboration with merge requests;
Complete continuous integration (CI) and continuous deployment/delivery (CD) pipelines to build, test, and deploy your applications;
Each project can also have an issue tracker, issue board, and a wiki.

GitLab has been used by more than 100,000 organizations, and it's the most popular solution to manage Git repositories on-premises.

2、Jenkins

Jenkins Source Code Repository

Jenkins is one of the best open-source continuous integration and automation server due to the over 1,800 plugins to support creating, delivering, and automating any project.

Using Jenkins to automate your development workflow will help you to focus on the work that matter most.
Jenkins is commonly used for:

Building projects
Running tests
Static code analysis
Deployment

You can execute repetitive tasks, save time, and optimize your development process with Jenkins.

3、Argo CD

Argo CD Source Code Repository

Argo CD is a declarative, continuous delivery tool for Kubernetes, which uses the principle of GitOps.
GitOps is a principle of using Git as the "single source of truth" for application deployment information.
It ensures that the state of a deployment is the same as the state which is defined in the Git repository.

Why should you use Argo CD？

Application definitions, configurations, and environments should be declarative and version controlled.
Application deployment and lifecycle management should be automated, auditable, and easy to understand.

4、Tekton

Tekton Source Code Repository

Tekton is a powerful yet flexible Kubernetes-native open-source framework for creating CI/CD systems.
It's open-source and part of the CD Foundation, a Linux Foundation project.

The main project with Tekton is Tekton Pipelines. It provides k8s-style resources for declaring CI/CD-style pipelines.
The Tekton Pipelines are cloud-native and decoupled:

Run on Kubernetes;
Have Kubernetes clusters as a first-class type;
Use containers as building blocks;
One Pipeline can be used to deploy to any k8s cluster;
The Tasks which make up a Pipeline can easily be run in isolation;
Resources such as git repositories can easily be swapped between runs.

5、Ansible

Ansible Source Code Repository

Ansible is a radically simple IT automation system.
It handles configuration management, application deployment, cloud provisioning, ad-hoc task execution, network automation, and multi-node orchestration.
Ansible makes complex changes like zero-downtime rolling updates with load balancers easy.

While Ansible leverages IaC, it uses SSH for its push nodes, so it's agentless.
Ansible is very easy to use for its Playbooks are written in YAML that is readable by humans.

The Design Principles of Ansible are:

Have an extremely simple setup process with a minimal learning curve;
Manage machines quickly and in parallel;
Avoid custom agents and additional open ports, be agentless by leveraging the existing SSH daemon;
Describe infrastructure in a language that is both machine and human-friendly;
Focus on security and easy auditability/review/rewriting of content;
Manage new remote machines instantly, without bootstrapping any software;
Allow module development in any dynamic language, not just Python;
Be usable as non-root;
Be the easiest IT automation system to use, ever.

In a nutshell, Ansible is one of the most simple yet effective IT orchestration and configuration management tools.

6、Helm

Helm Source Code Repository

Maybe you are already using Docker and Kubernetes, which are the basis of containerization.
After that, you will need a mechanism to manage the Kubernetes resources. Yes, helm can help you to achieve this.

Helm is a tool that streamlines installing and managing Kubernetes applications. Think of it like apt/yum/homebrew for Kubernetes.

Helm renders your templates and communicates with the Kubernetes API.
Helm runs on your laptop, CI/CD, or wherever you want it to run.
Charts are Helm packages that contain at least two things:
- A description of the package (Chart.yaml)
- One or more templates, which contain Kubernetes manifest files
Charts can be stored on disk, or fetched from remote chart repositories (like Debian or RedHat packages)

You can use Helm to:

Find and use popular software packaged as Helm Charts to run in Kubernetes;
Share your own applications as Helm Charts;
Create reproducible builds of your Kubernetes applications;
Intelligently manage your Kubernetes manifest files;
Manage releases of Helm packages.

In addition, Helm is a CNCF graduated project.

7、Harbor

Harbor Source Code Repository

Harbor is an open-source trusted cloud native registry project that stores, signs, and scans content.
Harbor extends the open-source Docker Distribution by adding the functionalities usually required by users such as security, identity and management.
Having a registry closer to the build-and-run environment can improve image transfer efficiency.
Harbor supports the replication of images between registries and also offers advanced security features such as user management, access control and activity auditing.

The 8 main features of Harbor:

Cloud native registry: With support for both container images and Helm charts, Harbor serves as a registry for cloud-native environments like container runtimes and orchestration platforms.
Role-based access control: Users access different repositories through 'projects' and a user can have different permission for images or Helm charts under a project.
Policy-based replication: Images and charts can be replicated (synchronized) between multiple registry instances based on policies with using filters (repository, tag and label). Harbor automatically retries a replication if it encounters any errors. This can be used to assist load-balancing, achieve high availability, and facilitate multi-datacenter deployments in hybrid and multi-cloud scenarios.
Vulnerability Scanning: Harbor scans images regularly for vulnerabilities and has policy checks to prevent vulnerable images from being deployed.
LDAP/AD support: Harbor integrates with existing enterprise LDAP/AD for user authentication and management, and supports importing LDAP groups into Harbor that can then be given permissions to specific projects.
Image deletion & garbage collection: System admin can run garbage collection jobs so that images(dangling manifests and unreferenced blobs) can be deleted and their space can be freed up periodically.
Graphical user portal: User can easily browse, search repositories and manage projects.
Easy deployment: Harbor can be deployed via Docker compose as well Helm Chart, and a Harbor Operator was added recently as well.

Helm is a CNCF graduated project too.

8、Sonarqube

Sonarqube Source Code Repository

SonarQube empowers developers to write cleaner and safer code.
It can catch tricky bugs to prevent undefined behavior from impacting end-users and make sure your codebase is clean and maintainable, to increase developer velocity.

You can integrate Sonarqube scanning into the Jenkins/Tekton Pipeline to catch code issues as they occur in the CI process.

9、Prometheus

Prometheus Source Code Repository

Prometheus is the second graduated project of CNCF. It is a systems and service monitoring system.
It collects metrics from configured targets at given intervals, evaluates rule expressions, displays the results,
and can trigger alerts when specified conditions are observed.

The features that distinguish Prometheus from other metrics and monitoring systems are:

A multi-dimensional data model (time series defined by metric name and set of key/value dimensions);
PromQL, a powerful and flexible query language to leverage this dimensionality;
No dependency on distributed storage; single server nodes are autonomous;
An HTTP pull model for time series collection;
Pushing time series is supported via an intermediary gateway for batch jobs;
Targets are discovered via service discovery or static configuration;
Multiple modes of graphing and dashboarding support;
Support for hierarchical and horizontal federation.

10、DevStream

DevStream Source Code Repository

We've gone through 9 DevOps tools, and maybe at this moment you are thinking that DevOps tools are too much and these make you feel overwhelmed.
Maybe you wish you could have an open-source tool to help you manage those DevOps tools. You choose the best DevOps tools that you love,
then one tool could take care of the rest. Ok, DevStream do is it.

DevStream is a DevOps toolchain manager. It can help you to kick off DevOps quickly and easily.

With DevStream, you can define your desired DevOps tools in a single human-readable YAML config file, and at the press of a button (one single command),
you will have your whole DevOps toolchain and SDLC workflow set up.

Summary

At the last, I have to tell you some more bit about the DevOps tools I mentioned above. They are the top 10 tools just in my mind.
If you have a different "top 10" idea, that's fine.
I also welcome you to post your "top 10" in the comment section below.

Getting Started with minikube

Daniel Hu — Sat, 23 Apr 2022 15:22:39 +0000

What’s up guys, this is Daniel! Yeah, this English blog is WRITTEN by me, not TRANSLATED by me! It’s my first English blog in my whole life. If you are a Chinese reader, maybe you’ve ever seen my Chinese blogs before. Right, I wrote a lot of blogs, but only in Chinese. Believe it or not, English isn’t my strong suit. But I want to have a try today and I’ll do my best. Let’s get started.

What We Will Talk about Today

If you ask me how to create a local Kubernetes cluster, I'll tell you Kind, minikube, and Kubeadm are all good choices. If you ask me which tool is the most recommended for beginners, my answer must be minikube or Kind. minikube is more powerful than Kind, and Kind is easier than minikube.

In my previous article, I walked you guys through "How to Create a Local Kubernetes Cluster from the Ground Up" with Kind. If you are interested, here's a quick link for you:

Creating a Local Kubernetes Cluster from the Ground Up

You might ask why that article is written by Tiexin Guo, not me. Of course! As I said in the beginning, this blog you are reading now is my first English blog. So, technically, the one above isn’t “my” article, but I did write the Chinese version of it:

从零开始快速搭建本地 Kubernetes 测试环节

Both minikube and Kind are the most well-known and popular choices to run a Kubernetes environment on a local computer. Since I've shown you how to use Kind, I might as well introduce minikube to youadorable today.

Quick Start with `minikube`

minikube is a command-line tool like Kind that you can use to create and configure Kubernetes clusters locally on your computer.

How to Install `minikube`

If your computer is the same as mine, Mac with m1 chip, you can install the latest minikube stable release in 2 steps:

curl -LO https://storage.googleapis.com/minikube/releases/latest/minikube-darwin-arm64
sudo install minikube-darwin-arm64 /usr/local/bin/minikube

If you are using Homebrew, just one command:

brew install minikube

If your computer is of other platforms or architectures, see the “Installation” section in minikube start for more details.

`minikube start`

Like the section title we used here, to start using minikube, run minikube start:

$ minikube start
😄  minikube v1.25.2 on Darwin 12.2.1 (arm64)
👎  Unable to pick a default driver. Here is what was considered, in preference order:
    ▪ docker: Not healthy: "docker version --format {{.Server.Os}}-{{.Server.Version}}" exit status 1: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?
    ▪ docker: Suggestion: Start the Docker service <https://minikube.sigs.k8s.io/docs/drivers/docker/>
💡  Alternatively you could install one of these drivers:
    ▪ hyperkit: Not installed: exec: "hyperkit": executable file not found in $PATH
    ▪ parallels: Not installed: exec: "prlctl": executable file not found in $PATH
    ▪ vmware: Not installed: exec: "docker-machine-driver-vmware": executable file not found in $PATH
    ▪ virtualbox: Not installed: unable to find VBoxManage in $PATH
    ▪ podman: Not installed: exec: "podman": executable file not found in $PATH

❌  Exiting due to DRV_DOCKER_NOT_RUNNING: Found docker, but the docker service isn't running. Try restarting the docker service.

Ok, it doesn’t matter; we need to install Docker. In my previous article How to Create a Local Kubernetes Cluster from the Ground Up, I introduced how to "Install Docker".

After the Docker is installed, what we'll need in total?

A not too bad computer;
Internet connections;
Container or virtual machine hypervisor, such as: Docker, Hyper-V, KVM, VirtualBox, or VMware Workstation ...

Let's try to run minikube start again. This command is time-consuming the first time you use it, especially if the network speed is low. Feel free to have a cup of coffee then come back to see the result.

2000 years later...

Well Done! 0 error, 0 warning! The logs are beautiful!

$ minikube start
😄  minikube v1.25.2 on Darwin 12.2.1 (arm64)
✨  Automatically selected the docker driver
👍  Starting control plane node minikube in cluster minikube
🚜  Pulling base image ...
💾  Downloading Kubernetes v1.23.3 preload ...
    > preloaded-images-k8s-v17-v1...: 419.07 MiB / 419.07 MiB  100.00% 8.54 MiB
    > index.docker.io/kicbase/sta...: 28.23 MiB / 343.12 MiB  8.23% 1.34 MiB p/
    > index.docker.io/kicbase/sta...: 343.12 MiB / 343.12 MiB  100.00% 3.77 MiB
❗  minikube was unable to download gcr.io/k8s-minikube/kicbase:v0.0.30, but successfully downloaded docker.io/kicbase/stable:v0.0.30 as a fallback image
🔥  Creating docker container (CPUs=2, Memory=3885MB) ...
🐳  Preparing Kubernetes v1.23.3 on Docker 20.10.12 ...
    ▪ kubelet.housekeeping-interval=5m
    ▪ Generating certificates and keys ...
    ▪ Booting up control plane ...
    ▪ Configuring RBAC rules ...
🔎  Verifying Kubernetes components...
    ▪ Using image gcr.io/k8s-minikube/storage-provisioner:v5
🌟  Enabled addons: storage-provisioner, default-storageclass

❗  /usr/local/bin/kubectl is version 1.21.5, which may have incompatibilites with Kubernetes 1.23.3.
    ▪ Want kubectl v1.23.3? Try 'minikube kubectl -- get pods -A'
🏄  Done! kubectl is now configured to use "minikube" cluster and "default" namespace by default

Access Your Shiny Kubernetes Cluster

Do you have kubectl installed? If yes, you can now use it to access your shiny Kubernetes cluster:

$ kubectl get pod -A
NAMESPACE     NAME                               READY   STATUS    RESTARTS        AGE
kube-system   coredns-64897985d-hdmqd            1/1     Running   0               3m10s
kube-system   etcd-minikube                      1/1     Running   0               3m24s
kube-system   kube-apiserver-minikube            1/1     Running   0               3m25s
kube-system   kube-controller-manager-minikube   1/1     Running   0               3m25s
kube-system   kube-proxy-nkzmn                   1/1     Running   0               3m10s
kube-system   kube-scheduler-minikube            1/1     Running   0               3m23s
kube-system   storage-provisioner                1/1     Running   1 (2m40s ago)   3m22s

Alternatively, minikube can download the appropriate version of kubectl with the command minikube kubectl:

minikube kubectl -- get pod -A
    > kubectl.sha256: 64 B / 64 B [--------------------------] 100.00% ? p/s 0s
    > kubectl: 52.82 MiB / 52.82 MiB [--------------] 100.00% 6.04 MiB p/s 8.9s
NAMESPACE     NAME                               READY   STATUS    RESTARTS       AGE
kube-system   coredns-64897985d-hdmqd            1/1     Running   0              4m32s
kube-system   etcd-minikube                      1/1     Running   0              4m46s
kube-system   kube-apiserver-minikube            1/1     Running   0              4m47s
kube-system   kube-controller-manager-minikube   1/1     Running   0              4m47s
kube-system   kube-proxy-nkzmn                   1/1     Running   0              4m32s
kube-system   kube-scheduler-minikube            1/1     Running   0              4m45s
kube-system   storage-provisioner                1/1     Running   1 (4m2s ago)   4m44s

Cooooool!

Are you thinking this command is too complicated? Use the config below and you'll be happy:

alias kubectl="minikube kubectl --"

I'm used to command-line to access the Kubernetes cluster. Yes, I never use the Kubernetes Dashboard. But if you like to have some insight into your cluster state with a Dashboard, minikube bundles it for you:

$ minikube dashboard
🔌  Enabling dashboard ...
    ▪ Using image kubernetesui/dashboard:v2.3.1
    ▪ Using image kubernetesui/metrics-scraper:v1.0.7
🤔  Verifying dashboard health ...
🚀  Launching proxy ...
🤔  Verifying proxy health ...
🎉  Opening http://127.0.0.1:51801/api/v1/namespaces/kubernetes-dashboard/services/http:kubernetes-dashboard:/proxy/ in your default browser...

At this time, your browser will automatically open a new tab, and the Dashboard will soon show up:

Deploy an Application in Your Shiny Kubernetes Cluster

Let’s create a sample deployment with the image preslavmihaylov/kubehelloworld:latest and expose it on port 3000.

The minikube start told us to use the k8s.gcr.io/echoserver:1.4 to launch the hello-minikube application, but it'll fail on a Mac with m1 chip. See this issue for more details.

$ kubectl create deployment sample-deploy --image=preslavmihaylov/kubehelloworld:latest
deployment.apps/sample-deploy created
$ kubectl expose deployment sample-deploy --type=NodePort --port=3000
service/sample-deploy exposed
$ kubectl get pod
NAME                             READY   STATUS    RESTARTS   AGE
sample-deploy-795887588d-flkgb   1/1     Running   0          50s
$ kubectl get svc
NAME            TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)          AGE
kubernetes      ClusterIP   10.96.0.1      <none>        443/TCP          66m
sample-deploy   NodePort    10.107.59.38   <none>        3000:32631/TCP   43s

Then we can use kubectl to forward the port:

$ kubectl port-forward service/sample-deploy 3000:3000
Forwarding from 127.0.0.1:3000 -> 3000
Forwarding from [::1]:3000 -> 3000

Open the browser, visit localhost:3000, and "Hello World!" will soon show up.

Another way to access this service is to use the minikube service sample-deploy command and minikube will launch a browser page for you with the right url:port address.

And we can use the command minikube tunnel to use the LoadBalancer type Service. Here is an example:

$ kubectl delete service sample-deploy
service "sample-deploy" deleted
$ kubectl expose deployment sample-deploy --type=LoadBalancer --port=3000
service/sample-deploy exposed

In another terminal window, start the tunnel to create a routable IP with the command minikube tunnel:

$ minikube tunnel
✅  Tunnel successfully started

📌  NOTE: Please do not close this terminal as this process must stay alive for the tunnel to be accessible ...

🏃  Starting tunnel for service sample-deploy.

Now you can use the EXTERNAL-IP to access the Service:

$ kubectl get svc
NAME            TYPE           CLUSTER-IP      EXTERNAL-IP   PORT(S)          AGE
kubernetes      ClusterIP      10.96.0.1       <none>        443/TCP          86m
sample-deploy   LoadBalancer   10.96.205.167   127.0.0.1     3000:31945/TCP   28s
$ curl 127.0.0.1:3000
Hello World!

How to Manage the Cluster

I'll show you some commands here:

minikube pause # Pause Kubernetes cluster without impacting any deployed resources.
minikube unpause # Unpause the Paused Kubernetes cluster.
minikube stop # Remember the minikube start? Need I say more?
minikube config set memory 20480 # Change the default memory limit (requires a restart).
minikube addons list # Browse the easily installed Kubernetes addons catalog.
minikube start -p aged --kubernetes-version=v1.16.1 # Create a second cluster running an older Kubernetes version.
minikube delete --all # Yeah, delete all, delete anything, delete all clusters.

That's all?

No! But if you want to know them all, I'll show you the command docs here.

How to Push Images into a `minikube` Cluster

There are about 8 ways you can use to push images into a minikube cluster. And I'll show you the most useful two ways today.

Push Images with the `cache` Command

minikube cache add [flags] [options] # Add an image to local cache.

Cache? Yes, the image will be cached by minikube and automatically pushed into all clusters, not like the Kind method: kind load docker-image <IMAGE> [IMAGE...] [flags].

Let's see how many sub-commands cache has:

$ minikube cache -h
Add, delete, or push a local image into minikube

Available Commands:
  add         Add an image to local cache.
  delete      Delete an image from the local cache.
  list        List all available images from the local cache.
  reload      reload cached images.

Easy, isn't it?

The only sub-command we need to talk about might be reload. If your image changed after you had cached it, you need to execute minikube cache reload [flags] [options]

E.g.:

minikube cache add alpine:latest # Cache alpine:latest for all clusters.
minikube cache reload alpine:latest # Reload alpine:latest if it's changed.
minikube cache list # Display what images we have added to the cache.
minikube cache delete alpine:latest # Just delete alpine:latest

Pushing Directly to the In-Cluster Docker Daemon

If the image we want to use inside the minikube cluster is built locally instead of pulled from a registry, we can reuse the Docker daemon inside the minikube cluster. Yeah, we don’t have to build the image on our host machine and cache it; we can just build inside the same docker daemon inside the minikube cluster.

$ docker ps
CONTAINER ID   IMAGE                    COMMAND                  CREATED       STATUS       PORTS                                                                                                                                  NAMES
170fe8252660   kicbase/stable:v0.0.30   "/usr/local/bin/entr…"   6 hours ago   Up 6 hours   127.0.0.1:50981->22/tcp, 127.0.0.1:50982->2376/tcp, 127.0.0.1:50984->5000/tcp, 127.0.0.1:50985->8443/tcp, 127.0.0.1:50983->32443/tcp   minikube

$ eval $(minikube docker-env)
$ docker ps
CONTAINER ID   IMAGE                            COMMAND                  CREATED       STATUS       PORTS     NAMES
de4fedaf4ef0   preslavmihaylov/kubehelloworld   "docker-entrypoint.s…"   5 hours ago   Up 5 hours             k8s_kubehelloworld_sample-deploy-795887588d-flkgb_default_2e6b194a-bdc7-44cc-b455-91959a4206a9_0
d45474ce1888   k8s.gcr.io/pause:3.6             "/pause"                 5 hours ago   Up 5 hours             k8s_POD_sample-deploy-795887588d-flkgb_default_2e6b194a-bdc7-44cc-b455-91959a4206a9_0
...

What happened?

After the command eval $(minikube docker-env) is executed, docker accesses the docker daemon inside the minikube cluster! What's the secret with minikube docker-env command? Let's dig into it:

$ minikube docker-env
export DOCKER_TLS_VERIFY="1"
export DOCKER_HOST="tcp://127.0.0.1:50982"
export DOCKER_CERT_PATH="/Users/danielhu/.minikube/certs"
export MINIKUBE_ACTIVE_DOCKERD="minikube"

# To point your shell to minikube's docker-daemon, run:
# eval $(minikube -p minikube docker-env)

I don't think I need to explain more about what happened. And we can build against the Docker inside minikube now. Just execute a command like docker build -t my-image:latest ., my-image:latest is instantly accessible to the Kubernetes cluster.

How to …

Oops, there are many how-tos we could talk about, but I believe that you can start using minikube now. Maybe I'll talk about more how-tos next time. If you want to dive into minikube now, go ahead and study the official documentation.

Summary

Cool, I finished writing this blog, It's like opening Pandora's box; I love this feeling. Of course, I know this blog is at the primary-school-student level, but I believe I can do better and better.

Don’t forget to give a Like, Comment, and Subscribe! I’ll see you in the next article!

DEV Community: Daniel Hu

Top 10 Open-Source DevOps Tools That You Should Know

Wait, what’s the DevOps?

Top 10 Open-Source DevOps Tools Rundown

1、GitLab CE

2、Jenkins

3、Argo CD

4、Tekton

5、Ansible

6、Helm

7、Harbor

8、Sonarqube

9、Prometheus

10、DevStream

Summary

Getting Started with minikube

What We Will Talk about Today

Quick Start with minikube

How to Install minikube

minikube start

Access Your Shiny Kubernetes Cluster

Deploy an Application in Your Shiny Kubernetes Cluster

How to Manage the Cluster

How to Push Images into a minikube Cluster

Push Images with the cache Command

Pushing Directly to the In-Cluster Docker Daemon

How to …

Summary

Quick Start with `minikube`

How to Install `minikube`

`minikube start`

How to Push Images into a `minikube` Cluster

Push Images with the `cache` Command