mirror of
https://github.com/siderolabs/talos.git
synced 2025-08-15 11:07:03 +02:00
d6309eed66
Docs generation switched to v0.14 folder. Signed-off-by: Andrey Smirnov <andrey.smirnov@talos-systems.com>
62 lines
2.2 KiB
Markdown
62 lines
2.2 KiB
Markdown
---
|
|
title: "Customizing the Root Filesystem"
|
|
description: ""
|
|
---
|
|
|
|
The installer image contains [`ONBUILD`](https://docs.docker.com/engine/reference/builder/#onbuild) instructions that handle the following:
|
|
|
|
- the decompression, and unpacking of the `initramfs.xz`
|
|
- the unsquashing of the rootfs
|
|
- the copying of new rootfs files
|
|
- the squashing of the new rootfs
|
|
- and the packing, and compression of the new `initramfs.xz`
|
|
|
|
When used as a base image, the installer will perform the above steps automatically with the requirement that a `customization` stage be defined in the `Dockerfile`.
|
|
|
|
For example, say we have an image that contains the contents of a library we wish to add to the Talos rootfs.
|
|
We need to define a stage with the name `customization`:
|
|
|
|
```docker
|
|
FROM scratch AS customization
|
|
COPY --from=<name|index> <src> <dest>
|
|
```
|
|
|
|
Using a multi-stage `Dockerfile` we can define the `customization` stage and build `FROM` the installer image:
|
|
|
|
```docker
|
|
FROM scratch AS customization
|
|
COPY --from=<name|index> <src> <dest>
|
|
|
|
FROM ghcr.io/talos-systems/installer:latest
|
|
```
|
|
|
|
When building the image, the `customization` stage will automatically be copied into the rootfs.
|
|
The `customization` stage is not limited to a single `COPY` instruction.
|
|
In fact, you can do whatever you would like in this stage, but keep in mind that everything in `/` will be copied into the rootfs.
|
|
|
|
> Note: `<dest>` is the path relative to the rootfs that you wish to place the contents of `<src>`.
|
|
|
|
To build the image, run:
|
|
|
|
```bash
|
|
docker build --squash -t <organization>/installer:latest .
|
|
```
|
|
|
|
In the case that you need to perform some cleanup _before_ adding additional files to the rootfs, you can specify the `RM` [build-time variable](https://docs.docker.com/engine/reference/commandline/build/#set-build-time-variables---build-arg):
|
|
|
|
```bash
|
|
docker build --squash --build-arg RM="[<path> ...]" -t <organization>/installer:latest .
|
|
```
|
|
|
|
This will perform a `rm -rf` on the specified paths relative to the rootfs.
|
|
|
|
> Note: `RM` must be a whitespace delimited list.
|
|
|
|
The resulting image can be used to:
|
|
|
|
- generate an image for any of the supported providers
|
|
- perform bare-metall installs
|
|
- perform upgrades
|
|
|
|
We will step through common customizations in the remainder of this section.
|