Containers in Depth – Understanding how containers work to better work with them
summary
Explains how images are stacks of read only layers with a top read‑write container layer, shows Docker commands used (docker build pull run inspect history) and where data lives (var/lib/docker), describes storage drivers (aufs btrfs zfs devicemapper and the now‑default overlay2), demonstrates copy‑on‑write and union mounts, notes layers are content‑addressed with sha‑256 digests, and warns about a practical ceiling of about 128 layers and how overlays avoid inode exhaustion.
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chapters (21)
- 0:00Intro
- 2:26What are Containers?
- 6:56Creating and tracking layers to images
- 9:10How do layers & images intersect with the operating system?
- 13:36cgroups (control groups) • Groups processes for the purpose of system resource management
- 14:22namespaces
- 16:18How do we think about this?
- 17:40Containers can reuse layers . Docker commands can reuse layers if they already exist in the docker file structure
- 19:08Mapping layers to the file system (1.10+)
- 22:19Docker on Windows
- 22:32Root Folder
- 22:56Storage Drivers (aka Graphdrivers)
- 23:53Storage Driver Examples
- 26:45Storage Driver Tech
- 28:12Overlay Model
- 31:05Overlay Filesystem Directories Lower Dir
- 32:48What happens when we pull an image?
- 35:39Looking at layers #1 (LowerDir)
- 38:42Mapping History to Filesystem
- 39:47What happens when we create a container • Use docker run to start a container
- 42:23Open Container Initiative (OCI)
