Linux

Before and after Fedora releases, there are updates that keep coming in to fix bugs or add minor features to packages included in Fedora. To ensure that these are stable and don't affect the performance of the existing system, we do "update testing". Once testing is complete, we share our results and make sure that the developer is aware about the bugs and the success rate of the package. This article will explain how to participate in update testing and...

Release validation testing is a process which takes place before the official Fedora release. (Fedora is the upstream, community project from which RHEL is built.) Before the Final (GA) release, we have Alpha and Beta pre-releases and at each of these milestones, nightly builds (nightlies) and composes are released and tested to ensure that the release meets quality standards. Release validation testing is one way you can help Fedora get better, and this post will talk about how you can...

In the world of containers, there is a desperate need to be able to scan container images for known vulnerabilities and configuration problems, and as we proliferate containers and bundled applications into the enterprise, many groups and companies have started to build container scanning tools. Even Red Hat has been building a scanning tool based on the tried and true OpenSCAP project, but there were several problems we saw time and again. The problems with existing container scanning tools included...

Much has changed in the IT world in the last few years, first Microsoft Loves Linux and now Red Hat Loves .NET. I suspect for many of you it is a bit bewildering, however, there are huge wins here for software developers. C# is rapidly becoming the programming language with the greatest number of target platforms, including: iOS, Android, OSX, and now through the partnership with Red Hat (home of the worlds' most popular enterprise Linux platform) C# is becoming...

Rebase-helper is a tool that helps Linux package maintainers update their to the latest upstream version. New maintainers and experts alike will find value in the convenience this tool can offer. Rebase-helper applies patches, packages, and reports differences between the patched and un-patched versions.In summary, it automates some of the manual tasks usually performed by package maintainers when a new upstream version of that package is released. This article will explain how to get started using rebase-helper, and also demonstrate...

The classic 1984 movie Ghostbusters offered an important safety tip for all of us: " Don't cross the streams." - "Why not?" - "I t would be bad." - " I’m fuzzy on the whole good/bad thing. What do you mean, 'bad'?" - "Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light." - "Right. That’s bad. Okay. All right. Important safety tip. Thanks..." Similarly, in computing...

Special thanks to Red Hat's Petr Viktorin for sharing this bit of clever code. #! /usr/bin/python3 -O # finite_function_recursion:lazy_runtime_recoding:raw_unicode_escape from functools import partial def main(): """Print an encouraging message to stdout""" print() for m in get_strings(): print(m) print() def get_strings(c=0): """Return list of strings to display to the user""" I = L = C = s = 0 S = o( 41825590960378124374546057353963710973031568, 1128197075877756693608173239149061571294131523370094467240707291316, 28634919999905333837375431815649071658638057502987522288563421, 365227113932356026740958928599365475099366847504156564532, 10832, 9648, 1547030252077890721054968240874293402, 6848886034432315113697, 1026545237296201918476380, 136341829649174, 3484359852033570050171, 10968655762475855182, 39478210171221680, 3160248663052126290380, 3160029950901936033378, ) z, Z =...

Back in November we announced that we would be partnering with Microsoft to make a supported version of .NET available for Red Hat Enterprise Linux. Since then we’ve been working together to make sure that .NET runs great on RHEL and has the capabilities that enterprise developers require. Today, at Microsoft Build, we were invited to join Scott Hanselmann on stage where we demonstrated some of that work and showed how the partnership is helping to create a more stable...

May 2019 UPDATE - The no-cost developer subscription now includes RHEL 8. Today, Red Hat announced the availability of a no-cost Red Hat Enterprise Linux developer subscription, available as part of the Red Hat Developer Program. Offered as a self-supported, development-only subscription, the Red Hat Enterprise Linux Developer Suite provides you with a more stable development platform for building enterprise applications - across cloud, physical, virtual, and container-centric infrastructures. Red Hat SVP Craig Muzilla added some good points in his...

I first started using computers in the mid-80’s. A DOS-based computer, where - as a programmer - I had to first learn how to type and how to navigate a seemingly arcane series of commands. There was no mouse back in those days. Today, as a developer, I spend most of my day on a Windows or Mac OSX-based laptop and use Linux within a virtual machine (VM) inside a hypervisor like VirtualBox or Hyper-V. Even with years of experience...

We are heading to Moscone in San Francisco. Yes, for DevNation in June, but we are there for Microsoft Build 2016 this week. We’ve got many exciting things planned - some below and some you will need to wait and see - but as a first time sponsor of Build we are looking forward to welcoming the .NET audience to Red Hat Developers. All the details are here but here are some of the highlights: Red Hat Developers team will...

Recently I was asked to look into an issue related to QEMU's I/O subsystem performance - specifically, I was looking for differences in performance between glibc's malloc and other malloc implementations'. After a good deal of benchmarking I was unable to see a clear difference between our malloc (glibc) and others, not because the implementations were similar, but because there was too much noise in the system; the benchmarks were being polluted by other things, not just in QEMU, but...

Abstract This project (part of Red Hat Lab Q) was initiated by Jan Zeleny to accommodate low-end and low-cost devices, which have usually slower hardware, and has particular usefulness to Fedora. Three students (Josef Řídký, Michal Ruprich, Šimon Matěj) from Faculty of Information Technology (FIT VUT Brno, Czech Republic) began work on the project with me (Petr Hracek) as a leader of the team. The aim Let’s say we have a device with low-cost hardware and we have Fedora/EPEL Linux...

Occasionally, there's a need for a new GNU C Library for a given application to run. For example, some versions of the Google Chrome browser started to warn users on Red Hat Enterprise Linux 7 that future versions of Chrome would not support their operating system. The Chromium source code contained a version check, flagging all versions of the GNU C Library (glibc) older than 2.19 as obsolete. This check has since been relaxed to 2.17 (the version in Red...

2015 is coming to a close and it’s always fun to reflect on all that has changed, grown, and news that almost make you wonder if pigs can now fly. Our team has greatly expanded, the community is growing, we are now accepting content contributors from around the world...so much to pick from. As you can tell it’s been a busy year and here are just some of top highlights. Here we go and in no particular order: 1) A...

Red Hat Software Collections (RHSCL) 2.0 brings Perl 5.20 as a Docker image. This allows you to deploy Perl applications easily. The basic idea is to combine your application code from Git tree and Red Hat's rhscl/perl-520-rhel7 base image into an application image that will run your application in mod_perl environment. Your application can either be a simple Common Gateway Interface (CGI) script or a full-fledged Perl Web Server Gateway Interface (PSGI) application. Following this step-by-step procedure will show you...

Today, Red Hat announced the general availability of Red Hat Software Collections 2.1, Red Hat’s newest installment of open source web development tools, dynamic languages, and databases. Delivered on a separate lifecycle from Red Hat Enterprise Linux with a more frequent release cadence, Red Hat Software Collections bridges developer agility and production stability by helping to accelerate the creation of modern applications that can then be more confidently deployed into production. Red Hat Software Collections 2.1 features several new and...

Personally, I find it difficult to remember which SCLs ( software collections) I have enabled while I am doing development. Or, perhaps more likely, when I get distracted from development and I come back to the window I was using before. As a result, I added the following to my bashrc which displays in the prompt what SCLs are enabled. if [ "$X_SCLS" ]; then PRETTY_SCLS=${X_SCLS// /,} PRETTY_SCLS=${PRETTY_SCLS/%,/} PS1="($PRETTY_SCLS) $PS1" fi Someday, maybe I'll figure out the fancy that is...

New RHSCL-based Docker images that are now in beta let you easily build your own application containers even without writing any Dockerfiles. Here is an example of a Ruby on Rails application built with the Ruby 2.2 image using the PostgreSQL 9.4 image as a database backend. For building the application image we will use a tool called source-to-image (s2i, formally sti) which is a program that can build your application image on top of s2i images. For example the...

Today, we are pleased to announce the beta availability of Red Hat Software Collections 2.1, Red Hat’s newest installment of open source web development tools, dynamic languages, and databases. Delivered on a separate lifecycle from Red Hat Enterprise Linux with a more frequent release cadence, Red Hat Software Collections bridges developer agility and production stability by helping to accelerate the creation of modern applications that can then be more confidently deployed into production. Red Hat Software Collections 2.1 Beta helps...

Our Red Hat Developers program team has just concluded a "Time to Hello World" project to reduce the time it takes you to download and install a new technology, and then get to your first "hello world" application. By utilizing multiple resources from Red Hat engineering, UX, evangelists, docs, testing, and yes, even customers, this is just one of many Red Hat activities underway to minimize speed bumps when trying a new Red Hat technology. So, is 6 minutes quick...