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PE Static

This document explains how to configure static routes on PE devices. In static routing, data packets are given a clear path to destinations. This method is essential in controlled networks, where secure traffic flow is required. This guide compares CE with static routing configurations and guides PE implementation.

The specific commands may be different, but the basic concepts and procedures are the same.

Link to CE Static Routing Documentation: CE Static Routing Document

Basic Description​

Static routing on PE devices means manually adding entries to the routing table. This sends traffic through fixed routes instead of dynamic routing protocols. This is useful when the network is static or has special requirements. This requires adding the destination network, subnet mask, gateway IP, and outgoing interface.

CE static routing is basically the same, but PE configurations are more complex and depend on the service provider.

PE Static Route Configuration (Conceptual Analogy to CE)​

This table compares PE and CE static route settings..

Field (Conceptual)Description (Analogous to CE)
Destination IP AddressThe IP address of the destination network.
Subnet MaskThe subnet mask associated with the destination network.
Gateway IP AddressThe IP address of the next-hop router or interface.
Output InterfaceThe interface on the PE device through which traffic will be forwarded.
Priority/MetricDetermines the preference of this route compared to others. Lower values indicate higher priority.
Administrative DistanceUsed to distinguish between routes from different routing sources.
Route TagOptional tag for route identification and policy application.

Configuration Scenarios (Conceptual)​

The following scenarios illustrate how static routes might be applied on PE devices, paralleling the CE scenarios:

  • Two CEs Linked via a Single PE:
    • Static routes from CE to PE direct traffic between CE LANs.
    • PE acts as an intermediary and forwards packets based on configured routes.
    • PE bridge interfaces or VLANs can be used as interfaces.
  • Two CEs Linked via Different PEs:
    • Each PE device has static routes to send traffic to the remote CE network.
    • Gateway IP addresses point to the next PE device.
    • Routing between PEs can be done via MPLS or direct L3 connectivity.
  • Standalone CE Routing:
    • PE Static Routes: Used to send traffic from CE to a specific location.
    • Gateway IP: Points to a network device.
    • PE Ethernet Interface: Used for output.
  • Hub-and-Spoke VPNs (OpenVPN/IPSec):
    • PE static routes facilitate traffic in hub-and-spoke VPNs.
    • Routes send traffic to a VPN tunnel or gateway.
    • Advertisement routes provide route information to other devices.
  • Adding a Third CE:
    • Add routes to PE devices so that all CEs can communicate.
    • Change PE routes to match the new network.
    • Use the WAN IP of the CE as the next hop.
  • Editing/Deleting Routes:
    • Like CE routing, PE devices can change static routes.
    • Network administrators can change routing as needed.