3 ms·

It's not about docker, it about systemd-nspawn which is systemd's own alternative to docker. I'm with you here, at first I didn't understand the alarm but now

by vruiz 12y ago

It's not about docker, it about systemd-nspawn which is systemd's own alternative to docker. I'm with you here, at first I didn't understand the alarm but now I'm starting to see the danger of this trend.

ris 12y ago
I don't think systemd is moving into this territory just for fun. I seem to recall it's because now the kernel is moving towards unified cgroups-trees if systemd wants to be able to use cgroups it more or less has to be "in charge" of them at the root, meaning it's going to have to take care of this sort of functionality.
- jacquesm 12y ago
  Linux should simply adopt jails and get it over with rather than to get stuck in NIH territory.
  - ris 12y ago
    Right. They should "port" a feature that's intricately linked with the internal workings of a kernel over from another completely alien kernel.
    - jacquesm 12y ago
      Nobody said it would be easy.
      - ris 12y ago
        You... more or less implied it
  - dezgeg 12y ago
    Cgroups are not a virtualization / containerization feature like jails, their use cases are entirely different.
- digi_owl 12y ago
  Last i read on LWN the cgroups kernel dev was backing away from the idea of having a singular cgroups management daemon. And no, its not just for fun. RH is betting big on competing with Amazon and MS on cloud services. It would not surprise me if they are trying to get old RHEL server customers to move their servers onto the RH cloud with the switch to RHEL7.
  - sciurus 12y ago
    What Red Hat cloud?
    - digi_owl 12y ago
      http://www.redhat.com/en/technologies/cloud-computing http://www.redhat.com/en/technologies/cloud-computing
      - sciurus 12y ago
        That doesn't answer the question. To clarify, what I meant was that Red Hat doesn't run a public IaaS cloud to which people can "move their servers".
geofft 12y ago
I'm not super familiar with either, but as I understand it, systemd-nspawn is only an alternative to "docker run". The docker command supports all sorts of other things, like creating container images, manipulating, uploading, etc. systemd-nspawn just runs things, and the upstream docs suggest using debootstrap, yum, etc. to create a thing for nspawn to run. (Running things is both the easy part, and the part that most makes sense for an initsystem / system daemon to do.) systemd-import will grab Docker images from the internet, but I'm not sure it will do very much else. In other words, even if you adopt systemd's way of doing things in deployment, your developers are still using the docker command.
- justincormack 12y ago
  Well thats kind of why Rocket from CoreOS is writing specs and splitting these things up [1] so you can use different tooling. [1] https://github.com/appc/spec/blob/master/SPEC.md https://github.com/appc/spec/blob/master/SPEC.md

by vruiz 12y ago

ris 12y ago

I don't think systemd is moving into this territory just for fun. I seem to recall it's because now the kernel is moving towards unified cgroups-trees if systemd wants to be able to use cgroups it more or less has to be "in charge" of them at the root, meaning it's going to have to take care of this sort of functionality.

jacquesm 12y ago
Linux should simply adopt jails and get it over with rather than to get stuck in NIH territory.
- ris 12y ago
  Right. They should "port" a feature that's intricately linked with the internal workings of a kernel over from another completely alien kernel.
  - jacquesm 12y ago
    Nobody said it would be easy.
    - ris 12y ago
      You... more or less implied it
- dezgeg 12y ago
  Cgroups are not a virtualization / containerization feature like jails, their use cases are entirely different.
digi_owl 12y ago
Last i read on LWN the cgroups kernel dev was backing away from the idea of having a singular cgroups management daemon. And no, its not just for fun. RH is betting big on competing with Amazon and MS on cloud services. It would not surprise me if they are trying to get old RHEL server customers to move their servers onto the RH cloud with the switch to RHEL7.
- sciurus 12y ago
  What Red Hat cloud?
  - digi_owl 12y ago
    http://www.redhat.com/en/technologies/cloud-computing http://www.redhat.com/en/technologies/cloud-computing
    - sciurus 12y ago
      That doesn't answer the question. To clarify, what I meant was that Red Hat doesn't run a public IaaS cloud to which people can "move their servers".

geofft 12y ago

I'm not super familiar with either, but as I understand it, systemd-nspawn is only an alternative to "docker run". The docker command supports all sorts of other things, like creating container images, manipulating, uploading, etc. systemd-nspawn just runs things, and the upstream docs suggest using debootstrap, yum, etc. to create a thing for nspawn to run. (Running things is both the easy part, and the part that most makes sense for an initsystem / system daemon to do.) systemd-import will grab Docker images from the internet, but I'm not sure it will do very much else. In other words, even if you adopt systemd's way of doing things in deployment, your developers are still using the docker command.

justincormack 12y ago
Well thats kind of why Rocket from CoreOS is writing specs and splitting these things up [1] so you can use different tooling. [1] https://github.com/appc/spec/blob/master/SPEC.md https://github.com/appc/spec/blob/master/SPEC.md