Backup interface

Dear Group,

I'm doing a practice lab and really stuck with "backup interface"
configuration. Would anyone please help to advise?

  Question: R5 -----------Ethernet --------- R4
                    |-----------Frame Relay---------|
      Ethernet link between R4 and R5 has been installed as a backup of the
Frame Relay circuit between them. backup interface should wait for 30s after
the FR int come up before disabled.

  My configuration:
      r5: interface Serial0/0
                backup delay 0 30
                backup interface FastEthernet0/1
                ip address 129.1.54.5 255.255.255.0
                encapsulation frame-relay
                frame-relay map ip 129.1.54.4 504 broadcast
                no frame-relay inverse-arp
                frame-relay lmi-type cisco
             interface FastEthernet0/1
                ip address 129.1.45.5 255.255.255.0
                duplex auto
                 speed auto
      R4: interface Serial0/0.54 point-to-point
              ip address 129.1.54.4 255.255.255.0
              frame-relay interface-dlci 405
             !
          interface FastEthernet0/0
            ip address 129.1.45.4 255.255.255.0
            duplex auto
            speed auto
Rack1R5(config-if)#do show ip int br
   Interface IP-Address OK? Method
Status Protocol
FastEthernet0/0 129.1.58.5 YES manual up
up
    Serial0/0 129.1.54.5 YES manual
up up
FastEthernet0/1 129.1.45.5 YES manual *standby mode
down *
    As in Cisco Configuration Guide (Dial), for the "backup interface"
configuration, it just need "backup int fa0/1" and "delay 0 30" are enough
but when I do a shut in S0/0, the Fa0/0 turned *disabled*:
 Rack1R5#show ip int br
Interface IP-Address OK? Method Status
Protocol
FastEthernet0/0 129.1.58.5 YES manual up
up
Serial0/0 129.1.54.5 YES manual administratively down
down
FastEthernet0/1 129.1.45.5 YES *manual standby mode/disabled
down *

And output of debug backup:
 Rack1R5(config-if)#
Jul 17 16:13:50.534: BACKUP(Serial0/0): event = primary interface shutdown
Jul 17 16:13:50.534: BACKUP(Serial0/0): secondary interface
(FastEthernet0/1) moved to standby
Jul 17 16:13:50.534: BACKUP(Serial0/0): changed state to "disabled"
Rack1R5(config-if)#
Jul 17 16:13:52.541: %LINK-5-CHANGED: Interface Serial0/0, changed state to
administratively down
Jul 17 16:13:53.543: %LINEPROTO-5-UPDOWN: Line protocol on Interface
Serial0/0, changed state to down
Jul 17 16:13:53.543: BACKUP(Serial0/0): event = primary interface went down
Jul 17 16:13:53.543: *BACKUP(Serial0/0): backup is currently disabled on
this interface*
Rack1R5(config-if)#

Am I missing something here? Why Fa0/0 do not come up as expected? :(.

Thanks and best Regards,
Khoa

Blogs and organic groups at http://www.ccie.net
Received on Sat Jul 18 2009 - 17:14:51 ART