User`s guide

150 XSR User’s Guide
Overview of Dial Backup Chapter 8
Configuring Dialer Services
XSR(config-if<D1>)#dialer map ip 10.10.10.3 9053617363
XSR(config-if<D1>)#encapsulation ppp
XSR(config-if<D1>)#ip address 10.10.10.1 255.255.255.0
XSR(config-if<D1>)#no shutdown
Overview of Dial Backup
The dialed backup feature provides a backup link over a dial line. The backup
link is brought up when failure occurs in a primary link, and is brought down
when the primary link is restored.
Dial Backup Features
 User controllable delay when the link is activated for backup, and
when the link is deactivated, that is, brought down.
 Dial backup is activated when the XSR detects link failure.
NOTE
Dial backup may not be activated if the XSR's link at local site is up and a
remote site’s link is down.
The XSR distinguishes one type of Link Failure:
 When configured, a backup link will be activated on detection of
primary link failure.
Sequence of Backup Events
The following sequence of events occurs when a primary link fails and a
backup line fails:
1 A Primary Link fails.
2 A link failure is detected. This link is configured for backup, and is
monitored.
3 The Backup function is notified about link failure.