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 vpp interfaces gre <greN>

Create a GRE interface where <greN> follows the naming convention gre1, gre2, etc.

set vpp interfaces gre <greN> remote <address>

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

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

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

Basic Example:

set vpp interfaces gre gre1
set vpp interfaces gre gre1 remote 203.0.113.2
set vpp interfaces gre gre1 source-address 192.168.1.1

Interface Configuration

Description and Administrative Control

set vpp interfaces gre <greN> description <description>

Set a descriptive name for the GRE interface.

set vpp interfaces gre <greN> disable

Administratively disable the GRE interface.

Tunnel Mode

set vpp interfaces gre <greN> mode <mode>

Configure the GRE tunnel operating mode:

point-to-point - Default mode for direct tunnel between two endpoints
point-to-multipoint - Allows multiple remote endpoints

Tunnel Type

set vpp interfaces gre <greN> 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

set vpp interfaces gre <greN> kernel-interface <interface-name>

Bind a kernel interface to the GRE tunnel for management and application compatibility.

For detailed information about kernel interface integration, see VPP Kernel Interfaces Configuration.

Configuration Examples

Layer 3 GRE Tunnel

# IPv4 GRE tunnel
set vpp interfaces gre gre1
set vpp interfaces gre gre1 description "Site-to-site tunnel"
set vpp interfaces gre gre1 remote 203.0.113.10
set vpp interfaces gre gre1 source-address 192.168.1.1
set vpp interfaces gre gre1 tunnel-type l3

Layer 2 GRE Tunnel (TEB)

# Transparent Ethernet Bridge
set vpp interfaces gre gre2
set vpp interfaces gre gre2 description "L2 extension tunnel"
set vpp interfaces gre gre2 remote 203.0.113.20
set vpp interfaces gre gre2 source-address 192.168.1.1
set vpp interfaces gre gre2 tunnel-type teb

IPv6 GRE Tunnel

# IPv6 endpoints
set vpp interfaces gre gre3
set vpp interfaces gre gre3 remote 2001:db8::2
set vpp interfaces gre gre3 source-address 2001:db8::1

Point-to-Multipoint Configuration

# Hub configuration for multiple spokes
set vpp interfaces gre gre4
set vpp interfaces gre gre4 mode point-to-multipoint
set vpp interfaces gre gre4 remote 0.0.0.0
set vpp interfaces gre gre4 source-address 192.168.1.1

Note

For point-to-multipoint mode, the remote address must be set to 0.0.0.0 to allow multiple remote endpoints.

GRE with Kernel Interface

# GRE tunnel with management interface
set vpp interfaces gre gre5
set vpp interfaces gre gre5 remote 203.0.113.30
set vpp interfaces gre gre5 source-address 192.168.1.1
set vpp interfaces gre gre5 kernel-interface vpptun5
set vpp kernel-interfaces vpptun5 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 vpp interfaces bridge br1
set vpp interfaces bridge br1 member interface gre2
set vpp interfaces bridge br1 member interface eth1