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New RancherOS Offers Lean Linux Functionality Within Docker Containers (rancher.com)

RancherOS is a lean Linux distribution aiming to offer "the minimum necessary to get Docker up and running," and tucking many actual Linux services into Docker containers. An anonymous Slashdot reader quotes Distrowatch: Josh Curl has announced the release of a new version of RancherOS [which] moves the project out of its alpha status and introduces new features, including an official Raspberry Pi image... "We're especially excited about this since it offers users a cheap method of getting started with Docker and RancherOS."

49 comments

  1. Simpon's already did it! by Anonymous Coward · · Score: 0

    Try it again!

  2. Ah, now 2017 by Anonymous Coward · · Score: 0

    Will be the year of Linux on the Open Range.

  3. For Raspberry Pi by Anonymous Coward · · Score: 0

    Best are here.
    ftp://ftp.freebsd.org/pub/FreeBSD/releases/ISO-IMAGES/11.0/

    Not interested in Dockers.

  4. daemons by Anonymous Coward · · Score: 1

    Thanks to Microsoft, nobody uses the word "daemons" to refer to non-interactive background processes. Even the Linux hipsters call them "services" now.

    Docker. Nice pants, you use to cover your asshole.

    1. Re: daemons by Anonymous Coward · · Score: 0

      Daemon means a lot more than non-interactive background process. A daemon forks, execs, and exits, leaving itself with no parent process, no supervision other than itself - they 'daemonize'. Launchd, systemd and Windows services provide supervision to these background processes. They truly are no longer daemons because they do not daemonize.

    2. Re: daemons by Anonymous Coward · · Score: 0

      Sorry, no, you're full of shit. The defining characteristic of a daemon is the lack of a controlling terminal. Parent process does not matter.

    3. Re: daemons by Anonymous Coward · · Score: 0

      Calm down. Like a bunch of other comp sci terms, daemons has more than one definition. It's a relatively new discipline (if you can even call it a discipline in its near chaotic state). There is no universally accepted vocabulary yet.

    4. Re: daemons by Anonymous Coward · · Score: 0

      What? I have been saying daemons since the early 90s. I know it was used before that. This shit isn't new. No matter how many times you hipsters try to reinvent the wheel.

  5. Re: Docker by Anonymous Coward · · Score: 0

    You linux guys used to make fun of "DLL hell"

    No, they didn't. These Linux guys are all under the age of 25. They don't know what DLL Hell means, and Linux is older than they are.

  6. "Official" image for x86-only OS on an ARM? by Anonymous Coward · · Score: 0

    I must be dense, but how could you possibly have an official image for an ARM based computer when Docker is only for x86 and x86_64? If everything has to be run on an emulator like QEMU, then this hardly seems like a real solution.

  7. ARM since at least 2011 by raymorris · · Score: 2

    By 2011, Docker had ARM support.
    https://github.com/docker/dock...

    1. Re:ARM since at least 2011 by Anonymous Coward · · Score: 0

      Wrong! Look at the releases: https://github.com/docker/docker/releases and you will see that Docker on ARM isn't officially supported yet; it is in RC status. For now, to get around that, you could run it on an emulator, use a custom build, or build it yourself. As for the containers, as you cannot run most base images and the hub isn't really platform agnostic, they either have to be emulated from the outside, emulated on the inside, or you find a specially made ARM container.

  8. No, it's lightweight virtualization / jail by raymorris · · Score: 3, Informative

    Docker is basically the fastest, lightest type of virtualization. Mainly it gets you a reasonably secure jail. The container contains the entire userland, the whole OS other than the kernel. Some people use this to run both Debian Linux and Android at the same time. Yeah dependencies are handled too, but that's not normally the point.

    1. Re:No, it's lightweight virtualization / jail by Anonymous Coward · · Score: 0

      Isn't this redundant? The OS maintains virtual memory addressing for each process. Dockers just waste ram because many of the same libraries now have to be mapped separately for each. Why not just run these programs as normal processes on the guest, and duplicate the host image as needed?

    2. Re:No, it's lightweight virtualization / jail by Anonymous Coward · · Score: 0

      Different library requirements can be readily met for different apps. Less dependency hell.

    3. Re:No, it's lightweight virtualization / jail by Anonymous Coward · · Score: 0

      Yes, but many executables use many of the same libraries. Dependencies are managed by the package manager. If you're suffering dependency hell today, you need a new distro.

    4. Re: No, it's lightweight virtualization / jail by Anonymous Coward · · Score: 0

      Docker is not virtualization just like wine is not an emulator .

    5. Re: No, it's lightweight virtualization / jail by CmdrTamale · · Score: 1

      Docker is not virtualization just like wine is not an emulator .

      "wine" has the self-referential/recursive attribute.

      Could someone please explain how "docker" exhibits this attribute.
      --
      I'd rather you do it wrong, than for me to have to do it at all.

  9. How dare they switch to formal terms by Anonymous Coward · · Score: 0

    "Muh jargon! Muh metaphor! Muh hacker culture!"

    1. Re: How dare they switch to formal terms by Anonymous Coward · · Score: 0

      Well that is the issue isn't it. Hipster millennial startup founders have destroyed the hacker culture that created the technology that they exploit for billions in profit.

    2. Re: How dare they switch to formal terms by Anonymous Coward · · Score: 0

      "Hacker culture" does not reject professionalism. Hipsters mean the ones that try to keep things *appear* sophisticated so they can maintain information asymmetry and pretend secret club.

    3. Re: How dare they switch to formal terms by epyT-R · · Score: 1

      "Hacker culture" does indeed reject 'professionalism' as the word is usually associated with pretentious grandstanding over certain codes of behavior and dress. It has little bearing on the things that "hacker culture" does respect: merit, self-reliance, and a desire to learn and master.

  10. booter floppy by KiloByte · · Score: 4, Insightful

    So they put their program on pid 1, on bare BIOS^Wkernel? Ah booters of the old times...

    And this line made me smile:

    System Docker replaces traditional init systems like systemd

    So CADTs are moving away from systemd as fast as they flocked to it, while the rest of us are smirking.

    --
    The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
    1. Re:booter floppy by Anonymous Coward · · Score: 0

      More that Rancher is a bit of a wink and a nudge towards the "pets vs cattle" sysadmin argument.

      Pets being the label for your traditional racked server. Carefully maintained and cared for to keep uptime high.

      Cattle being the new breed of servers in a container, where you spin up and kill of as many as you need to keep things working, come hell, high water, or a kid with a ddos botnet.

      Also it is a response to CoreOS, that is the systemd posterboy for the cattle admins right now. With a middle finger thrown in because of the fallout between Docker and systemd/RH devs that basically spurred the development of CoreOS in the first place.

    2. Re:booter floppy by Anonymous Coward · · Score: 0

      Way to go Docker and RancherOS!
      Good bye systemd!

    3. Re:booter floppy by Zontar+The+Mindless · · Score: 1

      You do mean "Cascade of Dyslexic Teens", right?

      --
      Il n'y a pas de Planet B.
    4. Re:booter floppy by Anonymous Coward · · Score: 2, Funny

      Nice to see legacy inits like System D being deprecated in favor of more modern approaches, there will be some resistances from system d grey beards who refuse to learn new things but they should be grateful someone is developing code code for them for free. If they don't like new shiny they should fork and go away, after all the code is available.

    5. Re:booter floppy by Anonymous Coward · · Score: 0

      If you're running everything under containers there'd be little need for any other init/service manager at all, since Docker itself effectively becomes one. Makes sense.

    6. Re:booter floppy by Anonymous Coward · · Score: 0

      I think he meant Pokemon Go

    7. Re:booter floppy by Anonymous Coward · · Score: 0

      It might be goodbye to systemd-init, but maybe not systemd, the longer the use systemd-udev the more likely that the remained of the systemd project will be present.

    8. Re:booter floppy by philipmather · · Score: 1

      It's Dockers all the way down!

      --
      Regards, Phil
    9. Re:booter floppy by Anonymous Coward · · Score: 0

      There's nothing traditional about systemd. Unless you mean "traditional Microsoft".

    10. Re:booter floppy by Lennie · · Score: 1

      That is exactly what they are doing.

      --
      New things are always on the horizon
    11. Re:booter floppy by Anonymous Coward · · Score: 0

      Yes that was the original Machiavellian thing systemd did under the hoods to destroy udev systematically , so that no one can get rid off systemd after few years!
      Bourgeoisie historically always thought they can keep fooling people forever!
      Then comes the liberator..... :-)

  11. Some memory is shared, sometimes uses $1 of RAM by raymorris · · Score: 2

    Sometimes shared libraries get only one copy in memory. In other cases, you can end up using more memory. Sometimes it's worth a few extra MBs of RAM.

    Personally, I've developed some expertise with kvm/qemu, so I tend to use full virtualization more often. Yes, it uses even more RAM. 512 MB of RAM costs me what, $3? I bill at $100/hour, so given the choice between using $3 of RAM or 30 minutes of my time, I'll spend the $3.

    1. Re:Some memory is shared, sometimes uses $1 of RAM by KiloByte · · Score: 1

      That 512MB RAM costs peanuts for a single virtual machine, yeah. But what if you run hundreds or more? Wasting 10% memory suddenly means you need 10% more hardware for the same number of customers if their VMs tend to have small CPU and I/O needs outside load spikes and thus need mostly RAM for adequate performance.

      --
      The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
    2. Re:Some memory is shared, sometimes uses $1 of RAM by Anonymous Coward · · Score: 1

      ... for the same number of customers if their VMs ...

      Docker is not a replacement for virtual machines. It probably isn't even secure to have multiple clients on a single Docker server, since they are less isolated than VMs.

      Instead, Docker is used to bundle an environment along with an application. It's like creating a somewhat lightweight (preferably single application) virtual server image and being able to run it anywhere with no changes needed, and with any programming language and stack you want. That alone is worth the extra resources spent in many use cases.

    3. Re:Some memory is shared, sometimes uses $1 of RAM by Anonymous Coward · · Score: 0

      Personally, I've developed some expertise with kvm/qemu, so I tend to use full virtualization more often. Yes, it uses even more RAM. 512 MB of RAM costs me what, $3? I bill at $100/hour, so given the choice between using $3 of RAM or 30 minutes of my time, I'll spend the $3.

      What? How are you comparing the cost of RAM with your time? Apples and oranges?

  12. Score: 5, Exceptional by Anonymous Coward · · Score: 1

    Nice to see legacy inits like System D being deprecated in favor of more modern approaches, there will be some resistances from system d grey beards who refuse to learn new things but they should be grateful someone is developing code code for them for free. If they don't like new shiny they should fork and go away, after all the code is available.

    Extended golf clap.

    Very nicely done.

  13. Best forward path for Rancher by Anonymous Coward · · Score: 0

    they need to drop the OS gimmicry and focus on delivering an interface. The biggest major drawback is their system container hack, which equates to no value given that swarm can run across multiple operating systems.

  14. Yes, unless it's many copies of the same image by raymorris · · Score: 1

    If it's hundreds of *different* images, that's a tradeoff to consider. If it's many copies of the same image, most memory can be shared. Every approach has advantages and disadvantages.

    Until you thousands of instances, the most expensive resource is probably people. RAM, CPU, and storage are cheaper than people, and you don't have to buy health insurance and other benefits for your RAM.

  15. So basically... back to LXC containers? by exabrial · · Score: 1

    So basically... back to LXC containers? Or am I missing something. Time to RTFA

  16. Re:Docker is... by kwerle · · Score: 4, Interesting

    Docker is a freeze dried VM with mappable ports and filesystem. It runs on several OSs on various platforms. I'm not sure what its killer feature is. It isn't just the ability to include libs with your program - it's a way to include the entire OS with your program - with all the libs and whatever else you need.

    Things I do with docker:
    * get rid of RVM/rbenv, NVM, and all those other version managers. Just fire up a docker container with the version of ruby/node/whaterver you want
    * package up services for deployment (web apps in my case) and toss the image to devops/IT to deploy
    * test tools/software I'm not familiar with - not sure if you want to install latest? fire up a docker container and take it for a spin. And when you're done testing, maybe just continue using the container.
    * run things on platforms that don't support them. Want to run redis on windows? docker container. Want to run git hubflow on windows without installing extra stuff? docker container.

  17. Not official, been working for years by raymorris · · Score: 1

    > isn't officially supported yet; it is in RC status. For now ... use a custom build, or build it yourself

    Yes, you can either download an unofficial build or compile it yourself, like people have been doing for years now. Gmail and Google Maps were officially beta for years, not officially supported as millions of people used them. You seem to confuse "officially supported" vs "works".

  18. Ubuntu Core by hackel · · Score: 1

    So this is basically just Ubuntu Core using docker containers instead of snaps?

    1. Re:Ubuntu Core by Anonymous Coward · · Score: 0

      Exactly. The simpler implementation of the same idea.

  19. Re:Docker is... by MikePikeFL · · Score: 1

    The deployment of services sounds interesting, but I have some questions.

    Do you have a common system/platform guide that includes hardening etc. for all possible dev OS choices?
    Do you have to have documentation for each type of possible dev teams preferred OS or is that all standardized on the dev side?
    Does devops/IT apply what they want to the OS before deploying? What if it breaks?

    Sorry I could be showing my age- most of my experience comes from the silo dev model (MGMT/DEV/QA/SEC). Everyone had tunnel vision and only cared that their part was minimally satisfied.

    You may have guessed where I sat in my silo by myself as a team with a "say" in that process (I am no longer part of that process thankfully).

    --
    "Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway" -Andrew Tanenbaum
  20. Re:Docker is... by kwerle · · Score: 1

    Some of your questions make more sense than others. In the context of deploying, docker looks a lot like a VM deployment - except instead of having to build up a VM using chef, and with all the luggage that usually entails, the docker image tends to only be running the service. Imagine a linux kernel with only one process running. So there aren't a lot of edges to harden. Usually the service image gets launched in something that looks like a DMZ behind a firewall with a loadbalancer in front of it.. In our case it's a little wild west.

    But part of the joy/ease of docker is that you build on some particular image. It would be easy to imagine an organization that was more .. organized than ours specifying a few base image flavors that developers would have to build off of - then you could harden those images all you wanted. I don't know that I would be a big fan of that, however. You can see where redhat supplies a lot of images, for example (https://access.redhat.com/search/#/container-images).

    Concrete (semi bogus) example: you want to run redis (maybe on windows - where it's not trivial). There is a redis docker image: https://hub.docker.com/_/redis...
    "docker run -p 6379:6379 redis"
    That will fire up a docker container running redis and will map the port on the image to the port on the docker host (usually localhost, these days). You can now connect to port 6379 and talk to redis. The container running redis is hard to describe - it's a full (stripped) linux system and it's only running that one process. You can fire up a shell on that container using another docker command and it has a bunch of the things you expect. Some shell (maybe bash or something lighter). Most of the filesystem stuff you expect. It's like a VM - if you built a VM to only run redis.

    I don't know if any of this helps - it really is a weird concept - at least I had a really hard time wrapping my head around it. But I do love what I can do with it.