At the recent Embedded Linux Conference in Portland, National Instruments software engineer Julia Cartwright, an acting maintainer on a stable release of the RT patch, gave a well-attended presentation called “What Every Driver Developer Should Know about RT.” Cartwright started with an overview of RT, which helps provide guarantees for user task execution for embedded applications that require a high level of determinism. She then described the classes of driver-related problems that can have a detrimental impact to RT, as well as potential resolutions.
“The Civil Infrastructure Platform is the most conservative of The Linux Foundation projects,” began Yoshitake Kobayashi at the recent Embedded Linux Conference in Portland. Yet, if any eyelids started fluttering shut in anticipation of an afternoon nap, they quickly opened when he added: “It may also be the most important to the future of civilization.”
The Linux Foundation launched the Civil Infrastructure Platform(CIP) project in April 2016 to develop base layer, open source industrial-grade software for civil infrastructure projects, starting with a 10-year Super Long-Term Support (SLTS) Linux kernel built around the LTS kernel. CIP expects to add other similarly reusable software building blocks that meet the safety and reliability requirements of industrial and civil infrastructure.
In this series, we are previewing the Cloud Foundry for Developers training course to help you better understand what Cloud Foundry is and how to use it. So far, we’ve covered:
The Cloud Foundry command-line interface (cf CLI) is your primary tool for interacting with your Cloud Foundry instances: manage apps, view logs, run health checks, manage buildpacks, manage users, and manage plugins. Today, we will learn how to install the tool and run commands. You’ll need a Cloud Foundry instance; see How Can I Try Out Cloud Foundry? to learn about some hosting providers to try, some of them free.
Installing cf
Install the cf CLI by following the instructions at Installing the cf CLI. Verify that it installed correctly by checking the version:
$ cf --version
cf version 6.30.0
Localization
The cf CLI supports localization. The default language setting is en-US. To change it follow the directions at Installing the cf CLI: Localize. This controls the language only for the cf CLI, and does not affect your system settings.
Getting Started with the cf CLI
The cf CLI has an inbuilt help system. cf --help displays the main help menu, and you can get help on specific commands with cf [command name] --help, for example:
$ cf login --help
Logging In
The first step to interacting with a Cloud Foundry instance, also called a target, is to log in. You are logging into an API endpoint, using this syntax: cf login api.cloudfoundry.system.domain. It will always have the api prefix.
For example, to log into Pivotal Web Services located at run.pivotal.io, your target is api.run.pivotal.io.
Orgs And Spaces
When you log in, you are asked to target an org and a space. If there is only one org and one space these become your default targets. When there are multiple orgs and spaces then you must specify the ones you want.
cf target displays your current API endpoint, user, org and space.
cf orgs prints a list of orgs that you can access.
cf target -o org switches to a different org.
cf spaces prints a list of spaces that you can access.
cf target -s space switches to a different space.
Correct cf CLI Version
It is possible for multiple Cloud Foundry targets to run different versions, so you should verify that your CLI version works with your current target. Use the cf curl command to determine version information.
All Cloud Foundry targets expose an info endpoint, which prints the release name, build number, description, and various endpoints. Run cf curl /v2/info to see this information, and look for the "min_cli_version". The version you installed should be equal to or newer than the "min_cli_version".
Debugging Connection Issues
The CF_TRACE environment variable prints API request diagnostics, showing your login API, cf CLI version, API version, and lot of other useful information. First set the environment variable, then run the cf target command:
$ export CF_TRACE=true
$ cf target
Unset it with export CF_TRACE=false. Or you can use it per command by prepending your commands:
$ CF_TRACE=true cf target
Now that you know the basics of using cf CLI, come back for the fifth and final blog to learn how to create and push a simple app.
These steps walk you through the process of setting up an SFTP server on Linux for the secure transfer of files for specialized file transfer-only users.
CentOS 7 or any Linux server distribution is a very powerful server that performs above and beyond what your business might need. Whatever task you throw at the server, it will be ready. And, if it isn’t ready out of the box, you can make it so.
Take, for instance, the ability to easily configure CentOS 7 to work as an SFTP server. If you aren’t sure about SFTP, it is the FTP service built into Secure Shell (SSH), which allows users to securely push and pull files to and from the server, using SSH. With CentOS 7, there’s no third party software to install to make this work—everything is installed out of the box. There is, however, a slight bit of work to be done to get this configured.
CoreOS, the Linux distribution and container management startup Red Hat acquired for $250 million earlier this year, today announced the Operator Framework, a new open source toolkit for managing Kubernetes clusters.
CoreOS first talked about operators in 2016. The general idea here is to encode the best practices for deploying and managing container-based applications as code. “The way we like to think of this is that the operators are basically a picture of the best employee you have,” Red Hat OpenShift product manager Rob Szumski told me. Ideally, the Operator Framework frees up the operations team from doing all the grunt work of managing applications and allows them to focus on higher-level tasks. And at the same time, it also removes the error-prone humans from the process since the operator will always follow the company rulebook.
If you spend much time on the Linux command line (and you probably wouldn’t be reading this if you didn’t), you’ve undoubtedly noticed that the ls command displays your files in a number of different colors. You’ve probably also come to recognize some of the distinctions — directories appearing in one color, executable files in another, etc.
How that all happens and what options are available for you to change the color assignments might not be so obvious.
Kubernetes is one of the highest velocity open source projects around, attracting more than 80,000 commits from nearly 3,000 developers at more than 1,180 companies over the past three years. From the start, the project has managed its success by gauging whether its users are excited about the technology and using it, which they are. Likewise, Craig McLuckie, CEO of Heptio and co-founder of Kubernetes remains excited about the technology.
Brian Redmond, Azure Architect on the Global Black Belt team at Microsoft, showed how to build CI/CD pipelines into Kubernetes-based applications in a talk at KubeCon + CloudNativeCon.
Kelsey Hightower, Developer Advocate at Google, kicked off the KubeCon + CloudNativeConevent in Austin with an opening keynote in which he demonstrated Kubernetes’ ease of use with the help of his smartphone. Apart from commending the audience for making Kubernetes the boring-in-a-good-way framework it is today, Hightower also warned about how Kubernetes should not be considered the end game, but a means to an end.
The ability to extend Kubernetes is its secret superpower, said Chen Goldberg, Director of Engineering at Google, speaking at the recent KubeCon + CloudNativeCon in Austin.
In the race to build tools that help engineers become more productive, Goldberg talked about how she once led a team that developed a platform that did just that. Despite the fact the platform initially worked, it was not extensible, and it was also difficult to modify.
