Specifications

Chapter 7 Configuring Frame Relay
ISDN as a Backup Connection with Floating Static Routes
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Cisco 1700 Series Router Software Configuration Guide
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ISDN as a Backup Connection with
Floating Static Routes
When the router makes routing decisions, static routes normally take precedence
over learned routes. If you have configured static routes, the router usually sends
data over these routes before using routes that it has learned and stored in the
routing table.
However, when the ISDN line is used as a backup connection and is configured
with static routes, the primary WAN connection (the Frame Relay line) does not
come back up when the ISDN line is used. Floating static routes enable the ISDN
line to use static routes to the central-site router until the main WAN connection,
the Frame Relay line, is active again.
This section describes how to configure ISDN to operate as a secondary, or
backup, WAN connection with floating static routes.
These are the major tasks in configuring your router:
• Configuring Global Parameters
• Configuring Security
• Configuring the Fast Ethernet Interface
• Configuring the Frame Relay Interface
• Configuring the Frame Relay Subinterface
• Configuring the ISDN Interface
• Configuring EIGRP Routing
• Configuring When the Router Dials Out
• Configuring Command-Line Access to the Router
Figure 7-4 shows the configuration example used in this section.