HP 7102dl - ProCurve Secure Router Configuration Manual page 150

Configuring Backup WAN Connections
Configuring a Persistent Backup Connection
555-1111
originate
Router A
Backup dial list
555-2222 PPP4
555-3333 PPP5
3-62
555-2222
answer-always
Router B
Backup dial list
555-1111 PPP2
555-3333
Router C
Figure 3-15. Backup Call Process
2. If the peer answers the call, the Secure Router OS sends the authentication
and negotiation protocols that have been configured for the backup PPP
interface. If the authentication and negotiation are successful, the backup
connection is established.
ProCurve# show running-config interface ppp 1
int ppp 1
backup call-mode originate
backup number 5552222 digital-64k 1 1 ppp 2
Router calls this
number.
Figure 3-16. Backup Settings for Dialing Out
Dialing out
Line failure
B doesn't
A calls
answer
555-2222
A calls
555-3333
Dialing in
Caller ID is
B receives
not 555-1111
call
B terminates
call
Router uses PPP 2 to place the
call and establish the
connection.
B answers
A negotiates
connection with
B using PPP4
Caller ID is
555-1111
B closes primary
connection and
uses PPP2 to
negotiate a backup
connection
Router places a
backup call if PPP
1 goes down.