📝 Docker Deep Dive - Notes
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Date: April 23, 2021

https://www.hanselminutes.com/784/doing-open-source-with-brian-douglas

Play With Docker
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A handy way to try weird things in docker is using play-with-docker <https://play-with-docker.com>. You get a four hour session for free, after four hours everything will be deleted, but you can start a new session.

### Installing Docker on Linux

Installing on Ubuntu.

[code]
  wget -qO- https://get.docker.com/ | sh

### Running Docker commands without sudo

In order to run docker commands without using sudo you need to add docker to your group.

[code]
  sudo usermod -aG docker ubuntu

Architecture and Theory
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Container - Isolated area of an OS with resource usage limits applied.

Namespaces and Control Groups are hard, which is why containers were unusable by mortals before docker.

Namespaces
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Isolation

Each container looks and feels like a regular OS. It has its own eth0, users, kernel. These are completely isolated from every other container running on the system.

Namespaces are analogous to what Hypervisors do on hardware.

- Process ID (pid)
- Network (net)
- Filesystem/mount (mnt)
- Inter-proc comms (ipc)
- UTS (uts)
- User (usr)

Control Groups
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Resource usage limits