Nydus-localdisk

Nydus localdisk is a new backend implementation of Nydus. This repo mainly contains tools and libraries related to localdisk image generation.

Overview

The localdisk backend can store nydus images to local raw disk. In this backend, each Nydus mirror corresponds to a block device, each layer of the mirror is mapped to a partition of the block device, and the partition is located through the GPT partition table.

Building

cd cmd/nydus-localdisk
go build

Usage

Nydus localdisk generator converts a Nydus image from the source registry to a gpt disk image file in localdisk format.

./nydus-localdisk convert --source $SOURCE --target $TARGET

If you only have an OCI image, you can use Nydusify to convert it to a Nydus image first, and then use this tool to generate a Nydus localdisk image file.

Import Library

import "github.com/adamqqqplay/nydus-localdisk/pkg/generator"

generator.ConvertImage(imagePath, workDir)

Example

We provide a shell script to test localdisk image mounts, you can find it in misc/test-localdisk.sh

1. Build Nydus localdisk generator.

git clone https://github.com/adamqqqplay/nydus-localdisk ~/nydus-localdisk
cd ~/nydus-localdisk/cmd/nydus-localdisk
go build
mv ./nydus-localdisk ~/nydus-localdisk/

2. Build Nydus that supports the localdisk backend.

git clone https://github.com/adamqqqplay/image-service
cd image-service
git checkout nydusd-localdisk-backend
make release
cp ./target/release/nydus* ~/nydus-localdisk/

3. Generate and test localdisk image.

cd ~/nydus-localdisk/
sudo nerdctl run -d --restart=always -p 5000:5000 registry
sudo nydusify convert --fs-version 6 --source ubuntu --target localhost:5000/ubuntu:nydus-v6
sudo ./nydus-localdisk convert --source localhost:5000/ubuntu:nydus-v6 --target ./ubuntu
./misc/test-localdisk.sh ./ubuntu/output.img

If you see output like this, it means the test was successful.

INFO Localdisk initialized at /dev/loop8, has 6 patitions, GUID: 28ecb493-f52b-4a8b-aa40-39991f31c21d