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today's howtos

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HowTos

  • Specify Name (Save As) When Saving File in vi / vim

    The vi (or vim) text editor is a very effective text editor for Linux / UNIX systems. It has been around since 1976 and you either love it or hate it. In order to be effective with the editor, it is important to know all the commands. One such command is specifying the name, or save as, of the file before you write it to disk. Let’s take a look at how to use the “save as” feature in vim.

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  • Josef Strzibny: Download RPM packages locally with DNF

    Sometimes, you only want to download RPM packages without installing them. This is now super easy with DNF.

    If you remember Yum, you had to resolve to installing a yum-plugin-downloadonly plugin or a separate tool to be able to download them for inspection.

  • Arturo Borrero González: Openstack Neutron L3 failover issues

    In the Cloud Services team at the Wikimedia Foundation we use Openstack Neutron to build our virtual network, and in particular, we rely on the neutron-l3-agent for implementing all the L3 connectivity, topology and policing. This includes basic packet firewalling and NAT.

    As of this writing, we are using Openstack version Train. We run the neutron-l3-agent on standard linux hardware servers with 10G NICs, and in general it works really well. Our setup is rather simple: we have a couple of servers for redundancy (note: upstream recommends having 3) and each server runs an instance of neutron-l3-agent. We don’t use DVR, so all ingress/egress network traffic (or north-south traffic) flows using these servers. Today we use a flat network topology in our cloud. This means that all of our virtual machines share the same router gateway. Therefore, we only have one software-defined router.

    Neutron does a very smart thing: each software-defined router is implemented on a linux network namespace (netns). Each router living on its own netns, the namespace contains all IP addresses, routes, interfaces, netfilter firewalling rules, NAT configuration, etc.

    Additionally, we configure the agents and software-defined routers to be deployed on an high availability fashion. Neutron implements this by running an instance of keepalived (VRRP) inside each router netns. The gateway IP is therefore a virtual address that can move between the two instances of the neutron-l3-agent.

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  • Prepare for successful container adoption with these tips

    IT teams use containers to build more dynamic applications and support modern microservice architectures. And containers are a critical tool for IT organizations to take advantage of innovations, such as cloud services, Agile methodology, DevOps collaboration and mobile apps.

    As businesses turn to containers to fuel development and support infrastructures, they must identify which workloads benefit from containerization, as well as strategize automation benefits and deploy the right tools for management.

    As a result, IT teams are better positioned to evaluate savings potential, adopt key DevOps processes and apply IT training where necessary. In this article, we explore containerization's history and its uses, assess ideal workloads, potential operational savings and key management approaches.

  • How to Install VirtualBox 6.1 On Linux?

    Virtual Machines are software used to run other operating systems within a pre-installed operating system. This self-contained OS runs as a separate computer that has no relation to the host OS. VirtualBox is an open-source cross-platform software that can help you run multiple guest operating systems on a single computer. In this article, let’s look at how to install VirtualBox 6.1 on Linux, easily.

    Why Install VirtualBox?

    One of the most important use cases of VirtualBox is its ability to try out/test various operating systems without fiddling with your internal storage. VirtualBox creates a virtual environment that utilizes system resources like RAM and CPU to power the OS inside a container.

More in Tux Machines

today's leftovers

     
  • What is Raspberry Pi 4 “Model B”? [Ed: I'm still waiting for them to formally apologise for going behind customers' backs, making secret deals with Microsoft to put Microsoft malware on all those devices]

    Raspberry Pi has conquered the world of SoC (System on a Chip). It has already garnered millions of followers since its release in 2012. Not only is it inexpensive, but it’s also versatile, modular, and multi-purpose. It has become popular not only as a credit-sized computer board but also as a controller in electronic, robotics, and IoT projects. The size, features, and price drive the popularity of the Pi, especially in the DIY community. To keep up with the current technological trends, the tiny board has undergone plenty of upgrades over the years, and there have been many varieties so it can cater to the needs and demands of its users. In 2019, the Raspberry Pi Foundation released the fourth generation of the multi-purpose board, the Raspberry Pi 4 B. It is the most powerful Pi to date, sporting huge upgrades from its predecessors. The compact board is touted to deliver a PC-level performance, and it didn’t disappoint.

  • Kentaro Hayashi: Grow your ideas for Debian Project

    There may be some "If it could be ..." ideas for Debian Project. If idea is concreate and worth to make things forward, it should make a proposal for Project Funding. [...] I'm not confident whether mechanism works, but Debian needs change.

  • Sam Thursfield: Calliope, slowly building steam

    There are some interesting complexities to this, and in 12 hours of hacking I didn’t solve them all. Firstly, Bandcamp artist and album names are not normalized. Some artist names have spurious “The”, some album names have “(EP)” or “(single)” appended, so they don’t match your tags. These details are of interest only to librarians, but how can software tell the difference? The simplest approach is use Musicbrainz, specifically cpe musicbrainz resolve-ids. By comparing ids where possible we get mostly good results. There are many albums not on Musicbrainz, though, which for now turn up as false positives. Resolving Musicbrainz IDs is a tricky process, too — how do we distinguish Multi-Love (album) from Multi-Love (single) if we only have an album name? If you want to try it out, great! It’s still aimed at hackers — you’ll have to install from source with Meson and probably fix some bugs along the way. Please share the fixes!

  • Neovide Is A Graphical Neovim Client Written In Rust

    Neovide is a really cool GUI client for Neovim. Although it essentially functions like Neovim in the terminal, Neovide does add some nice graphical improvements such as cursor animations and smooth scrolling. It even has me thinking about making it my new "vim" alias.

Linux 5.11.13, 5.10.29, 5.4.111, 4.19.186, 4.14.230, 4.9.266, and 4.4.266

Get involved with Mageia, become a Packager

With Mageia 8 just released and development for Mageia 9 getting underway in Cauldron, the unstable branch of Mageia, now is a great time to get involved with packaging. We are starting to look at the features that we want to include for Mageia 9, and as it is so early in the development cycle, now is the time for major developments, or big updates to key pieces of software. This is a great time to join the project as you can propose features you would like to see, help to implement large changes or see how a distribution evolves through development, stabilisation and then is released. If there is an application that you are interested in, if you want to help maintain part of the distribution, or if you want to learn something new, there are many opportunities to do so with the packaging team. Read more

Google does not want you to tell your players about your donation page

I recently updated Pixel Wheels banner image on Google Play. That triggered a review of the game: shortly after the update I received a message telling me Pixel Wheels was "not compliant with Google Play Policies". What nefarious activity does the game engage in? Sneak on users? Mine bitcoins? [...] Meanwhile you can still get the game from F-Droid or itch.io, since they do not have a problem with a link to a donation page. Read more