4 ms·

It's lighter in the sense that it should require less resources to keep each container running, but comparable in the sense that you still need to orchestrate h

by lojack 12y ago

It's lighter in the sense that it should require less resources to keep each container running, but comparable in the sense that you still need to orchestrate how services connect and how each container is configured.

geerlingguy 12y ago
This, exactly. I've heard many people talking about how Docker will put an end to a thousand different problems, especially regarding configuration management... But it really won't. You still need to be able to configure everything inside the container (thus the need for a CM tool), and then also the environment and infrastructure inside which the containers live (thus the need for infra management tools). Docker really doesn't make infrastructure management markedly easier—just faster, more flexible, and slightly more powerful. It's one layer of abstraction over a VM, IMO, and that's a good thing, but carries with it it's own set of complexities.
- skrebbel 12y ago
  > You still need to be able to configure everything inside the container (thus the need for a CM tool) I'm missing something, but in what scenarios would you need to do something more complex than what can be expressed in a few RUN and ADD commands in a Dockerfile? My limited experience is that indeed, orchestration is still completely needed. We underestimated that and now we have a bunch of hacky shell scripts that build and start and stop docker containers at various moments. But the docker containers themselves are pretty simple.
  - geerlingguy 12y ago
    It depends on what you're doing inside the containers themselves. If you're simply pulling from a git repo to update a code checkout, and installing one or two things via apt/yum, shell script/RUN isn't so bad. If you're approaching containers more like 'lightweight VMs', the string of RUN commands gets unmaintainable, fast. That can indicate some deeper problems, but in some circumstances (and especially when making updates to your container images), using configuration management for individual containers can be helpful for the same reasons even CM-ifying a small single-purpose standalone VM can.
- deleted 12y ago
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by lojack 12y ago

geerlingguy 12y ago

This, exactly. I've heard many people talking about how Docker will put an end to a thousand different problems, especially regarding configuration management... But it really won't. You still need to be able to configure everything inside the container (thus the need for a CM tool), and then also the environment and infrastructure inside which the containers live (thus the need for infra management tools). Docker really doesn't make infrastructure management markedly easier—just faster, more flexible, and slightly more powerful. It's one layer of abstraction over a VM, IMO, and that's a good thing, but carries with it it's own set of complexities.

skrebbel 12y ago
> You still need to be able to configure everything inside the container (thus the need for a CM tool) I'm missing something, but in what scenarios would you need to do something more complex than what can be expressed in a few RUN and ADD commands in a Dockerfile? My limited experience is that indeed, orchestration is still completely needed. We underestimated that and now we have a bunch of hacky shell scripts that build and start and stop docker containers at various moments. But the docker containers themselves are pretty simple.
- geerlingguy 12y ago
  It depends on what you're doing inside the containers themselves. If you're simply pulling from a git repo to update a code checkout, and installing one or two things via apt/yum, shell script/RUN isn't so bad. If you're approaching containers more like 'lightweight VMs', the string of RUN commands gets unmaintainable, fast. That can indicate some deeper problems, but in some circumstances (and especially when making updates to your container images), using configuration management for individual containers can be helpful for the same reasons even CM-ifying a small single-purpose standalone VM can.
deleted 12y ago
[deleted]