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Systemd vs. Docker

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Re: Systemd vs. Docker

#51

Post by qwertyuiop924 »

bryanlarsen wrote: post #6
pmoriarty wrote: post #2

CoreOS's Rocket is built around systemd? That alone disqualifies it for me right there.

Why the systemd hate? Because it's a big monolithic project that takes over your system? You do realize that Docker is much more monolithic and opinionated than systemd, right?

Yes, but I will never have to use docker if I don't want to. For that matter, docker doesn't try to be cron, it doesn't want to handle mounting, didn't subsume udev, and doesn't encourage other project to link against it, and to drop all compatibility with non-linux systems. Systemd does, did, and is doing that right now.

Re: Systemd vs. Docker

#52

Post by qwertyuiop924 »

bryanlarsen wrote: post #24
atemerev wrote: post #20

Earlier quoted context omitted.

Opinionated, yes. Monolithic, no. Huge mess of everything that deeply integrates in any system — of course not, your containers don't need to know anything about Docker and host system, you are absolutely free in choices. It's even possible to run (gasp!) multiple services with supervision inside Docker.

That's the first time I ever heard anybody argue that Docker isn't monolothic. It does everything inside it's single daemon executable. Compare against Rocket, which doesn't use a daemon, and uses separate executables for different tasks and stages.

Docker is monolithic, probably more so than it should be, but designed quite well, allowing for things like triton to exist. Systemd is monolithic, but does far more than docker, and really more than it should.

Re: Systemd vs. Docker

#53

Post by qwertyuiop924 »

baldfat wrote: post #42
jimktrains2 wrote: post #5

Earlier quoted context omitted.

Or they can move to one of the BSDs and use jails which are much more stable, secure, and tested than linux containers.

Exactly that is your choice. I am concerned about the drama of systemd by people that don't like systemd always peeing on every and anything that mentions systemd. It is in the old rpm vs deb, vim vs emacs, python vs perl dram of the past.

No, it isn't. Nobody is going to try to nuke my emacs install, and install vi on my machine instead. If vi started deleting emacs, or using non-utf8 encodings on all text for some reason, or otherwise made using emacs impossible, the vi developers would fix it, or the community would say, "What the FUCK!?" and probably fork it.

Re: Systemd vs. Docker

#54

Post by qwertyuiop924 »

4ad wrote: post #12
JohnDoe365 wrote: post #9

Earlier quoted context omitted.

Or they can move to a steam engine which are much more stable, secure, and tested than cars consuming gasoline. Embrace the change, it's for a better future.

> Embrace the change, it's for a better future. Unfortunately, especially when you also factor in the impact of ZFS and DTrace, you are moving into the past, not the future.

Quite.

Embrace the change of having less security, less control, and less capability to debug your software.

Re: Systemd vs. Docker

#55

Post by laumars »

xaduha wrote: post #47
laumars wrote: post #32

Earlier quoted context omitted.

Well if someone is competent enough to create a Docker image then it's not a great stretch to assume many of them would also be competent enough to create a jail. And FreeBSD is just as easy to use as Linux (actually, I generally find it easier to administrate than Linux since things are more rigorously laid out. But a lot of that is also down to my own personal preference). At the end of the day, both Jails and Dock…

You're missing the point. Even if jails is the most elegant, easy and powerful technology in the world it's still on BSD. People are not going to switch to BSD just because of jails. Sure, then can use both, but why? Docker and linux containers in general made things easier and more accessible for many. Switching from that to jails doesn't make sense.

> You're missing the point. Even if jails is the most elegant, easy and powerful technology in the world it's still on BSD. People are not going to switch to BSD just because of jails.

We're not just talking about jails though. The OP was discussing systemd + containers. Switching to FreeBSD to escape systemd isn't that weird of an idea since most of the same Linux software will also run on FreeBSD. In fact I'm seriously considering switching my Debian 7 (Wheezy) servers over to FreeBSD rather than upgrade to Debian 8 (Jessie) and have deal with systemd. Anecdotally I've read other people consider switching away from Linux as well

You might like systemd and Dockers. That's great. But that's your personal preference. You shouldn't be so surprised when other people might prefer to run the same software but on a different platform.

On a tangent note: I also have a bunch of existing systemd systems - RHEL servers, ArchLinux desktops, etc - that I'm very happy with and intend to keep running Linux. I make this point just to emphasise that I'm not anti-Linux nor a FreeBSD fanboy. Just someone who's platform agnostic.

> Sure, then can use both, but why?

Why not? This isn't a sports team where you're expected to only support one product. It's quite possible to use multiple different technologies based on whatever fits a specific purpose better.

Re: Systemd vs. Docker

#56

Post by qwertyuiop924 »

bryanlarsen wrote: post #36
atemerev wrote: post #30

Earlier quoted context omitted.

Docker is just a toolkit for composing and networking layered OS images. It improves isolation of things and adheres to simple principles (immutable containers, restarting instead attempting to recover, etc.) It structures things better. Inter-container communication is deliberately simple (env variables and, recently, networking). Systemd spits on isolation, it embraces integration of everything. Supervision, loggin…

Your criticism of systemd still applies to docker. "Supervision, logging, communication, IO, configuration, state management — everything goes through docker" If I use systemd I have to type 'systemd logs' to get at my logs, or I can use a plugin to move it somewhere else. If I use docker I have to type 'docker logs', or I can use a plugin to move it somewhere else. etc. etc. P.S. Agree completely with your praise of…

Wrong. Docker manages containers, and only containers. 'docker logs' shows you the logs from your containers. Docker never tried to make me run my non-container logs through 'docker logs'. You know what else docker never tried to be? cron. Or udev. Or consolekit. Or init. It just tries to manage your containers.

Re: Systemd vs. Docker

#57

Post by qwertyuiop924 »

vidarh wrote: post #38
atemerev wrote: post #30

Earlier quoted context omitted.

Docker is just a toolkit for composing and networking layered OS images. It improves isolation of things and adheres to simple principles (immutable containers, restarting instead attempting to recover, etc.) It structures things better. Inter-container communication is deliberately simple (env variables and, recently, networking). Systemd spits on isolation, it embraces integration of everything. Supervision, loggin…

Isolation and integration are not opposites. You can increase isolation (through e.g. judicious application of cgroups, which systemd encourages and makes use of) while also increasing integration (e.g. sharing APIs). Docker is to me far more problematic when it comes to integration. It is trying to make everything go through itself, without providing a fraction of the scheduling and management capabilities that syst…

Integration is all well and good, I suppose. Until you put all your integration into a single process, which will kill your system if it ever crashes. Then I will have some words to say about you. Especially if you ever, ever, EVER, EVER, EVER, use assert, in ANY situation you could ever potentially recover from.

Re: Systemd vs. Docker

#58

Post by xaduha »

laumars wrote: post #49
xaduha wrote: post #23

Earlier quoted context omitted.

> That's basically the argument to use Windows and Windows-based technology and not Linux. Not today it isn't. Years, maybe decades ago it could be. What Linux containers do is help to remove the barrier that various distributions introduced, it makes things more accessible and it's more lightweight than using virtualization. Centos, Alpine, Ubuntu, whatever. As long as it is in a container I can work with it. I can…

> But what jimktrains2 suggesting is complete opposite of that, it reduces options. Personally I'd consider having familiarity with more than one platform would increase one's options. But ultimately having other solutions on the market is a good thing. Not only because no one solution is the best at every metric (be it stability, security, speed, memory usage, nor any specific requirements), nor because different so…

What you're talking about is a luxury I can't afford. That's what I mean when I talk about the price. There are plenty of far more important technologies that I would rather learn.

I can't afford to learn two technologies that do about the same thing, of which one is significantly less popular, might now have tools that other has and runs on a significantly less popular OS.

Re: Systemd vs. Docker

#59

Post by xaduha »

laumars wrote: post #55
xaduha wrote: post #47

Earlier quoted context omitted.

You're missing the point. Even if jails is the most elegant, easy and powerful technology in the world it's still on BSD. People are not going to switch to BSD just because of jails. Sure, then can use both, but why? Docker and linux containers in general made things easier and more accessible for many. Switching from that to jails doesn't make sense.

> You're missing the point. Even if jails is the most elegant, easy and powerful technology in the world it's still on BSD. People are not going to switch to BSD just because of jails. We're not just talking about jails though. The OP was discussing systemd + containers. Switching to FreeBSD to escape systemd isn't that weird of an idea since most of the same Linux software will also run on FreeBSD. In fact I'm serio…

> Why not? This isn't a sports team where you're expected to only support one product.

Linux/Docker and BSD/jails aren't even in the same league.

Re: Systemd vs. Docker

#60

Post by laumars »

xaduha wrote: post #58
laumars wrote: post #49

Earlier quoted context omitted.

> But what jimktrains2 suggesting is complete opposite of that, it reduces options. Personally I'd consider having familiarity with more than one platform would increase one's options. But ultimately having other solutions on the market is a good thing. Not only because no one solution is the best at every metric (be it stability, security, speed, memory usage, nor any specific requirements), nor because different so…

What you're talking about is a luxury I can't afford. That's what I mean when I talk about the price. There are plenty of far more important technologies that I would rather learn. I can't afford to learn two technologies that do about the same thing, of which one is significantly less popular, might now have tools that other has and runs on a significantly less popular OS.

That's actually a fair point and one I completely sympathise with. But your original argument very much sounded like you were suggesting that people in general shouldn't bother with FreeBSD, jails, nor any other technologies which weren't dominant in their respective field. Which is why we disagreed.
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