A short introduction to LXC

A short introduction to LXC, an user space implementation of container on mainline linux, and the ecosystem around it

Transcript

1. A short introduction to LXC
   Ranjib Dey
   System Administrator,
   Bay Area Large-Scale Production Engineering – 02/20/2014
   

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2. Containers
   - Light weight virtualization
   - software based virtualization
   - userspace entity in mainline linux kernel (lxc)
   - built using kernel's containment facility
   

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3. Kernel facilities
   - namespaces
   - cgroups
   - capabilities
   

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4. Parts of a LXC container
   - rootfs
   - config
   - fstab
   - liblxc (dependency)
   

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5. Managing containers
   - create, destroy
   - start, stop (shutdown/kill, reboot)
   - freeze, unfreeze
   

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6. Customizing containers
   - template specific customizations
   - general configurations
   - cgroup related configurations
   - hooks
   - snapshots, overlayfs backed workflows
   - lxc-download pulls stock rootfs (CI backed)
   

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7. LXC packaging
   - liblxc is all you need to run
   - lxc-template offers linux distros
   - lxc all the binaries, stock configs
   

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8. Extending lxc
   - use template & download to build them
   - use config api to add run time configuration
   - build additional tools using any of the bindings
   - bindings: python, lua, ruby, Go.
   

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9. Extending lxc
   - simple example:
   #!/usr/bin/python3
   import lxc
   container = lxc.Container("my_container")
   container.create("ubuntu", {"release": "precise"})
   container.start()
   print(container.get_ips(timeout=10))
   container.shutdown(timeout=10)
   container.destroy()
   

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10. Extending lxc
    - more complex example:
    #!/usr/bin/ruby
    require 'chef/lxc'
    lxc "web" do
    template "ubuntu"
    recipe do
    package "apache2"
    service "apache2" do
    action [:start, :enable]
    end
    end
    action [:create, :start]
    end
    

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11. Whats next?
    - lxc 1.0 released today
    - better user namespace support
    - tools for extensible storage
    - union file system(aufs, overlayfs)
    - s3, gfs, swift/glance etc
    - CRIU & pr.haul
    - Docker, Maestro, Deis, Hroot etc
    

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12. Thank You
    @RanjibDey
    

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