NBD Server Implementation in Rust

This project implements a Network Block Device (NBD) server in Rust, following the NBD protocol specification. NBD allows a client system to use a remote block device as if it were a local disk.

Features

• Modern NBD protocol implementation (fixed newstyle negotiation)
• Support for multiple exports
• Configurable block sizes
• Export information handling including:
  • Export name
  • Description
  • Block size constraints (minimum, preferred, maximum)
  • Transmission flags
• Robust handshake protocol implementation
• Comprehensive logging

Prerequisites

• Rust
• Cargo package manager

Installation

Clone the repository and build the project:

git clone [repository-url]
cd nbd
cargo build --release

Usage

To run the NBD server:

cargo run --bin nbd-server -- [options]

Available options:

• -f, --file <FILE> - Path to the file to export
• -p, --port <PORT> - Port to listen on (default: 10809)
• -H, --host <HOST> - Host address to bind to (default: 127.0.0.1)
• -n, --name <NAME> - Export name (default: "export")
• -d, --description <DESC> - Export description (default: "NBD Export")

Supported Commands

The server supports the following NBD commands:

Handshake Phase Commands

• NBD_OPT_INFO - Request information about an export
• NBD_OPT_GO - Request to use an export
• NBD_OPT_LIST - List available exports
• NBD_OPT_ABORT - Abort the negotiation
• NBD_OPT_EXPORT_NAME - Legacy command to request an export

Transmission Phase Commands

• NBD_CMD_READ - Read data from the export
• NBD_CMD_WRITE - Write data to the export
• NBD_CMD_DISC - Disconnect from the server

Dependencies

• byteorder (1.5.0) - For handling endianness in network protocol
• clap (4.5.38) - For command-line argument parsing
• log (0.4) - For logging functionality
• env_logger (0.10) - For environment-based logging configuration

References

• NBD Protocol Documentation