RustBond

A Rust implementation of the MetalBond route distribution protocol.

MetalBond distributes virtual network routes across hypervisors over TCP/IPv6.

Features

• Async client/server with Tokio
• Automatic reconnection
• VNI-based subscriptions
• Multi-server HA with ECMP support
• Standard, NAT, and LoadBalancer route types
• Interoperable with Go MetalBond
• Optional netlink integration for kernel route installation

Quick Start

Server

use rustbond::{MetalBondServer, ServerConfig};

let server = MetalBondServer::start("[::]:4711", ServerConfig::default()).await?;
// ... server.shutdown().await?;

Client

use rustbond::{MetalBondClient, RouteHandler, Route, Vni};

struct MyHandler;
impl RouteHandler for MyHandler {
    fn add_route(&self, vni: Vni, route: Route) { /* handle add */ }
    fn remove_route(&self, vni: Vni, route: Route) { /* handle remove */ }
}

let client = MetalBondClient::connect(&["[::1]:4711"], MyHandler);
client.wait_established().await?;
client.subscribe(Vni(100)).await?;

Multi-Server (HA)

For high availability, connect to multiple servers simultaneously:

let client = MetalBondClient::connect(&["[::1]:4711", "[::1]:4712"], MyHandler);
client.wait_any_established().await?;
// Routes are deduplicated across servers; ECMP supported

Examples

# Run server (default: [::1]:4711)
cargo run --example server

# Run server on custom address
cargo run --example server -- -l [::]:4711

# Connect client to VNI 100
cargo run --example client -- -s [::1]:4711 -v 100

# Announce a route (VNI#prefix@nexthop)
cargo run --example client -- -s [::1]:4711 -v 100 -a "100#10.0.1.0/24@2001:db8::1"

# Multi-server HA (just add more -s flags)
cargo run --example client -- -s [::1]:4711 -s [::1]:4712 -v 100

Route Types

Announcement format: VNI#prefix@nexthop[#type[#fromPort#toPort]]

# Standard route (default) on VNI 100
"100#10.0.1.0/24@2001:db8::1"

# NAT route with port range on VNI 200
"200#10.0.2.0/24@2001:db8::2#nat#1024#2048"

# Load balancer target on VNI 100
"100#10.0.3.0/24@2001:db8::3#lb"

Kernel Route Installation (Netlink)

Enable the netlink feature to install routes directly into the Linux kernel routing tables:

# Install routes from VNI 100 to kernel routing table 100
cargo run --example client --features netlink -- \
  -s [::1]:4711 -v 100 \
  --install-routes 100#100 \
  --tun ip6tnl0

Options:

• --install-routes VNI#TABLE - Map VNI to kernel routing table (can be repeated)
• --tun DEVICE - Tunnel device name (default: ip6tnl0)

Routes are marked with protocol 254 for identification. Stale routes from previous runs are automatically cleaned up on startup.

Note: Requires root privileges to modify kernel routing tables.

Testing

cargo test           # All tests
cargo test --lib     # Unit tests only
cargo test --test integration  # Integration tests only

License

Licensed under Apache-2.0