VPP GRE Configuration

VPP GRE interfaces provide Generic Routing Encapsulation tunneling with high-performance packet processing. GRE tunnels encapsulate various protocols within IP packets, enabling connectivity across Layer 3 networks while maintaining the performance benefits of VPP’s optimized data plane.

Basic Configuration

Creating a GRE Interface

set interfaces vpp gre <vppgreN>

Create a GRE interface where <vppgreN> follows the naming convention vppgre1, vppgre2, etc.

set interfaces vpp gre <vppgreN> remote <address>

Set the tunnel remote endpoint address. Supports both IPv4 and IPv6 addresses.

set interfaces vpp gre <vppgreN> source-address <address>

Set the tunnel source address. Must match an address configured on the local system.

Basic Example:

set interfaces vpp gre vppgre1
set interfaces vpp gre vppgre1 remote 203.0.113.2
set interfaces vpp gre vppgre1 source-address 192.168.1.1

Interface Configuration

Description and Administrative Control

set interfaces vpp gre <vppgreN> description <description>

Set a descriptive name for the GRE interface.

set interfaces vpp gre <vppgreN> disable

Administratively disable the GRE interface.

Tunnel Type

set interfaces vpp gre <vppgreN> tunnel-type <type>

Set the GRE tunnel encapsulation type:

l3 - Generic Routing Encapsulation for network layer traffic (default).
teb - Transparent Ethernet Bridge for Layer 2 frame transport.
erspan - Encapsulated Remote Switched Port Analyzer for traffic mirroring.

Kernel Interface Integration

LCP kernel pair interface bound to the VPP GRE interface is created automatically. This allows standard Linux networking tools and services to interact with the VPP GRE.

IP Address Configuration

set interfaces vpp gre <vppgreN> address <ip-address/prefix>

Configure IPv4 or IPv6 addresses on the kernel interface. Multiple addresses can be assigned.

Examples:

# IPv4 address
set interfaces vpp gre vppgre0 address 192.168.1.10/24

# IPv6 address
set interfaces vpp gre vppgre0 address 2001:db8::10/64

MTU Configuration

set interfaces vpp gre <vppgreN> mtu <size>

Set the Maximum Transmission Unit (MTU) for the kernel interface. The MTU must be compatible with the connected VPP interface.

Example:

set interfaces vpp gre vppgre0 mtu 9000

Note

The MTU size must not exceed the MTU size supported by the associated VPP interface.

Configuration Examples

Layer 3 GRE Tunnel

# IPv4 GRE tunnel
set interfaces vpp gre vppgre1
set interfaces vpp gre vppgre1 description "Site-to-site tunnel"
set interfaces vpp gre vppgre1 remote 203.0.113.10
set interfaces vpp gre vppgre1 source-address 192.168.1.1
set interfaces vpp gre vppgre1 tunnel-type l3

Layer 2 GRE Tunnel (TEB)

# Transparent Ethernet Bridge
set interfaces vpp gre vppgre2
set interfaces vpp gre vppgre2 description "L2 extension tunnel"
set interfaces vpp gre vppgre2 remote 203.0.113.20
set interfaces vpp gre vppgre2 source-address 192.168.1.1
set interfaces vpp gre vppgre2 tunnel-type teb

IPv6 GRE Tunnel

# IPv6 endpoints
set interfaces vpp gre vppgre3
set interfaces vpp gre vppgre3 remote 2001:db8::2
set interfaces vpp gre vppgre3 source-address 2001:db8::1

GRE with Kernel Interface

# GRE tunnel with management interface
set interfaces vpp gre vppgre4
set interfaces vpp gre vppgre4 remote 203.0.113.30
set interfaces vpp gre vppgre4 source-address 192.168.1.1
set interfaces vpp gre vppgre4 address 10.0.1.1/30

Bridge Integration

GRE interfaces can be added as members to VPP bridges for Layer 2 switching. See VPP Bridge Configuration for detailed bridge configuration.

# Add TEB GRE tunnel to bridge
set interfaces vpp bridge vppbr1
set interfaces vpp bridge vppbr1 member interface vppgre2
set interfaces vpp bridge vppbr1 member interface eth1