Cisco Backup Interfaces Advantages / Disadvantages.

What IOS version are you running? I haven't tried it, but it seems to me that a 12000 GSR should be able to do SLA.

Hi Don,

Please see below the show version. I'm possitive that our GSR can't do SLA

Hostname#           show ver    
Cisco Internetwork Operating System Software
IOS (tm) GS Software (C12KPRP-K4P-M), Version 12.0(32)SY7, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2008 by cisco Systems, Inc.
Compiled Mon 29-Sep-08 14:02 by leccese
Image text-base: 0x00010000, data-base: 0x056B4000

ROM: System Bootstrap, Version 12.0(20040128:214555) [assafb-PRP1P_20040101 1.8dev(2.83)] DEVELOPMENT SOFTWARE
BOOTLDR: GS Software (C12KPRP-K4P-M), Version 12.0(32)SY7, RELEASE SOFTWARE (fc1)

 hostname uptime is 2 years, 48 weeks, 5 days, 12 hours, 8 minutes
Uptime for this control processor is 2 years, 48 weeks, 5 days, 8 hours, 30 minutes
System returned to ROM by reload at 00:04:45 GMT Fri Aug 7 2009
System restarted at 23:09:00 GMT Thu Aug 6 2009
System image file is "disk0:c12kprp-k4p-mz.120-32.SY7.bin"

cisco 12410/PRP (MPC7457) processor (revision 0x00) with 2097152K bytes of memory.
MPC7457 CPU at 1263Mhz, Rev 1.2, 512KB L2, 2048KB L3 Cache
Last reset from sw reset

Hi Experts,

I've configured 'backup interface' as described below. I want ethernet 1/5 to be the backup interface for fastethernet 0/0. I have configured the interfaces as such:

interface FastEthernet0/0
 description Hurricane Electric - To EGH PvX gig 11/3/8
 backup interface Ethernet1/5
 ip vrf forwarding internet-gw
 ip address 216.66.84.102 255.255.255.252
 load-interval 30
 carrier-delay 1
 duplex full
 speed 10
 no keepalive
 no cdp enable
end


interface Ethernet1/5
 ip vrf forwarding internet-gw
 ip address 216.66.85.105 255.255.255.252
 duplex full
end


When I do a show ip int brief I see the following on ethernet 1/5:

Ethernet1/5                216.66.85.105   YES manual standby mode          down

This is expected.

However, when I shut int fast 0/0, ethernet 1/5 becomes disabled:

Ethernet1/5                216.66.85.105   YES manual standby mode/disabled down

Can someone please help me determine whats I'm doing wrong?

Cheers

Carlton

OK Experts,

I have made this issue very simple for you guys to help me out.

I have two routers R22 and R23. I have configured the back up interface on R22 to be interface fas 0/1. Everything appears to be working fine. I issue the command show backup and I get the following on R22

r22#show backup
Primary Interface   Secondary Interface   Status
-----------------   -------------------   ------
FastEthernet0/0     FastEthernet0/1       normal operation
r22#

Also I get the following:

FastEthernet0/1            10.10.13.2      YES manual standby mode          down

However, when I shutdown interface fast 0/0 to test the back up interface fast 0/1 I get the following:

r22#show backup
Primary Interface   Secondary Interface   Status
-----------------   -------------------   ------
FastEthernet0/0     FastEthernet0/1       disabled
r22#

FastEthernet0/1            10.10.13.2      YES manual standby mode/disabled down


So it doesn't work.

Attached are the configs.

I was wondering if someone could help me figure out why this won't work.

Cheers

Carlton
20-15-29--r22-127.0.0.1-.txt
20-15-34--r23-127.0.0.1-.txt

Remove the backup interface command and verify that the links are all functional.

Hi Don,

I did as you suggested and links are all functional

According to the Cisco feature navigator, c12kprp-k4p-mz.120-32.SY7.bin supports SLA.

Hi Don,

Thanks for you continued help with this.

Cisco navigator may suggest is supports sla, however when I issue the command ip sla I get nothing back.

When I enter ip sla I should get the following:

Lab_EGH(config)#ip sla ?
  <1-2147483647>          Entry Number
  enable                  Enable Event Notifications
  ethernet-monitor        IP SLAs Auto Ethernet configuration
  group                   Group Configuration or Group Scheduling
  key-chain               Use MD5 authentication for IP SLAs Control Messages
  logging                 Enable Syslog
  low-memory              Configure Low Water Memory Mark
  reaction-configuration  IP SLAs Reaction-Configuration
  reaction-trigger        IP SLAs Trigger Assignment
  reset                   IP SLAs Reset
  responder               Enable IP SLAs Responder
  restart                 Restart An Active Entry
  schedule                IP SLAs Entry Scheduling


I don't get that with c12kprp-k4p-mz.120-32.SY7.bin. Any ideas why?

cheers