Backend.AI Storage Proxy

Backend.AI Storage Proxy is an RPC daemon to manage vfolders used in Backend.AI agent, with quota and storage-specific optimization support.

Package Structure

• ai.backend.storage
  • server: The agent daemon which communicates between Backend.AI Manager
  • api.client: The client-facing API to handle tus.io server-side protocol for uploads and ranged HTTP queries for downloads.
  • api.manager: The manager-facing (internal) API to provide abstraction of volumes and separation of the hardware resources for volume and file operations.
  • vfs
    • The minimal fallback backend which only uses the standard Linux filesystem interfaces
  • xfs
    • XFS-optimized backend with a small daemon to manage XFS project IDs for quota limits
    • agent: Implementation of AbstractVolumeAgent with XFS support
  • purestorage
    • PureStorage's FlashBlade-optimized backend with RapidFile Toolkit (formerly PureTools)
  • cephfs (TODO)
    • CephFS-optimized backend with quota limit support

Installation

Prequisites

• Python 3.8 or higher with pyenv and pyenv-virtualenv (optional but recommneded)

Installation Process

First, prepare the source clone of this agent:

# git clone https://github.com/lablup/backend.ai-storage-agent

From now on, let's assume all shell commands are executed inside the virtualenv.

Now install dependencies:

# pip install -U -r requirements/dist.txt  # for deployment
# pip install -U -r requirements/dev.txt   # for development

Then, copy halfstack.toml to root of the project folder and edit to match your machine:

# cp config/sample.toml storage-proxy.toml

When done, start storage server:

# python -m ai.backend.storage.server

It will start Storage Proxy daemon bound at 127.0.0.1:6021 (client API) and 127.0.0.1:6022 (manager API).

NOTE: Depending on the backend, the server may require to be run as root.

Filesystem Backends

VFS

Prerequisites

• User account permission to access for the given directory

XFS

Prerequisites

• Local device mounted under /vfroot
• Native support for XFS filesystem
• Access to root shell

Creating virtual XFS device for testing

Create a virtual block device mounted to lo (loopback) if you are the only one to use the storage for testing:

1. Create file with your desired size

# dd if=/dev/zero of=xfs_test.img bs=1G count=100

2. Make file as XFS partition

# mkfs.xfs xfs_test.img

3. Mount it to loopback

# export LODEVICE=$(losetup -f)
# losetup $LODEVICE xfs_test.img

4. Create mount point and mount loopback device, with pquota option

# mkdir -p /vfroot/xfs
# mount -o loop -o pquota $LODEVICE /vfroot/xfs

PureStorage FlashBlade

Prerequisites

• NFSv3 export mounted under /vfroot
• Purity API access

CephFS

Prerequisites

• FUSE export mounted unde /vfroot