Containers are a great way to deliver and run all kinds of applications. Although many people build containers for server applications, you can also use them for client applications on your local workstation. This helps when you want to test new applications without disrupting your existing system or when you use an immutable system such as Fedora Silverblue.
Podman takes this further by allowing you to run a client application without root access or daemons....
Wildcard certificates make it easy to secure lots of subdomains under a single domain. For example, you can secure web.example.com and mail.example.com with a single certificate for *.example.com. Fortunately, LetsEncrypt allows you to get wildcard certificates via a DNS ownership check (often called a DNS-01 challenge).
Fortunately, Traefik can request a certificate from LetsEncrypt automatically and complete the challenge for you. It can publish DNS records to multiple providers, but my favorite is Cloudflare....
Everyone has an opinion for the best way to manage containers, and there are many contenders depending on how much complexity you can handle and how much automation you require. One of my favorite ways to manage containers is docker-compose.
Overview of docker-compose docker-compose uses a simple YAML syntax to explain what your desired end state should look like. The compose specification covers all of the relevant configurations for containers, volumes, networks, and more....
When you build tons of kernels every day like my team does, you look for speed improvements anywhere you can. Caching repositories, artifacts, and compiled objects makes kernel builds faster and it reduces infrastructure costs.
Need for speed We use GitLab CI in plenty of places, and that means we have a lot of gitlab-runner configurations for OpenShift (using the kubernetes executor) and AWS (using the docker-machine executor). The runner’s built-in caching makes it easy to upload and download cached items from object storage repositories like Google Cloud Storage or Amazon S3....
Buildah and podman make a great pair for building, managing and running containers on a Linux system. You can even use them with GitLab CI with a few small adjustments, namely the switch from the overlayfs to vfs storage driver.
I have some regularly scheduled GitLab CI jobs that attempt to build fresh containers each morning and I use these to get the latest packages and find out early when something is broken in the build process....
My team at Red Hat depends heavily on GitLab CI and we build containers often to run all kinds of tests. Fortunately, GitLab offers up CI to build containers and a container registry in every repository to hold the containers we build.
This is really handy because it keeps everything together in one place: your container build scripts, your container build infrastructure, and the registry that holds your containers. Better yet, you can put multiple types of containers underneath a single git repository if you need to build containers based on different Linux distributions....
OpenShift deployments allow you to take a container image and run it within a cluster. You can easily add extra items to the deployment, such as environment variables or volumes.
The best practice for sensitive environment variables is to place them into a secret object rather than directly in the deployment configuration itself. Although this keeps the secret data out of the deployment, the environment variable is still exposed to the running application inside the container....
This post is the second installment in the series of What’s Happening in OpenStack-Ansible (WHOA) posts that I’m assembling each month. My goal is to inform more people about what we’re doing in the OpenStack-Ansible community and bring on more contributors to the project.
July brought lots of changes for the OpenStack-Ansible project and the remaining work for the Newton release is coming together well. Many of the changes made in the Newton branch have made deployments faster, more reliable and more repeatable....
The world of OpenStack moves quickly. Each day brings new features, new bug fixes, and new ways of thinking. The OpenStack-Ansible community strives to understand these changes and make them easier for operators to implement.
The OpenStack-Ansible project is a collection of playbooks and roles written by operators for operators. These playbooks make it easier to deploy, maintain, and upgrade an OpenStack cloud.
Keeping up with the changes in the OpenStack-Ansible project is challenging....
It seems like there’s a new way to run containers every week. The advantages and drawbacks of each approach are argued about on mailing lists, in IRC channels, and in person, around the world. However, the largest amount of confusion seems to be around security.
Launching secure containers I’ve written about launching secure containers on this blog many times before:
Launch secure LXC containers on Fedora 20 using SELinux and sVirt Improving LXC template security Try out LXC with an Ansible playbook CoreOS vs....