HSRP on a single router?

[moon_blue69]

I inherited the systems and on a single Cisco 1812 router I see this configuration. Could anyone kindly explain what this configuration is supposed to do? There are the only two interfaces which are configured on this router.

interface FastEthernet0
description External
ip address 192.168.255.19 255.255.255.248
no ip redirects
no ip unreachables
no ip proxy-arp
ip nat outside
ip virtual-reassembly
duplex auto
speed auto
standby delay reload 60
standby 8 ip 192.168.255.18
standby 8 preempt delay minimum 60 reload 60 sync 60
standby 8 name GL-HSRP-OUT
standby 8 track FastEthernet1
!
interface FastEthernet1
description Internal
ip address 192.168.98.204 255.255.255.240
no ip redirects
no ip unreachables
no ip proxy-arp
ip nat inside
ip virtual-reassembly
duplex auto
speed auto
standby delay reload 60
standby 9 ip 192.168.98.205
standby 9 preempt delay minimum 60 reload 60 sync 60
standby 9 name GL-HSRP-IN
standby 9 track FastEthernet0
!

[Georg Pauwen]

Hello,

the HSRP configuration, if this is the only router you have, doesn't make sense. You need at least two routers, simply because you cannot configure two IP addresses from the same subnet on the same router.

In your configuration, there are two different HSRP standby groups. My guess is that this is either a leftover from a network with multiple routers, or somebody starting and not finishing the entire config...

[tonypearce1]

"you cannot configure two IP addresses from the same subnet on the same router."

That's incorrect info :) Try this:
interface gi0/1
ip address 192.168.0.254 255.255.255.0
ip address 192.168.0.253 255.255.255.0 secondary
ip address 192.168.0.252 255.255.255.0 secondary

[Richard Burts]

You are correct that using secondary addresses you can configure several IP addresses in the same subnet on the same router. I believe that the point that Georg was trying to make is that you could not configure two addresses in the same subnet on two interfaces like

int gig0/0

ip address 192.168.0.253 255.255.255.0

int gig0/1

ip address 192.168.0.254 255.255.255.0

HTH

Rick

[paul driver]

Hello

show standby 
show standby brief

[moon_blue69]

Thanks Paul, Please find the requested config below.

Router-R1#show standby
FastEthernet0 - Group 8
State is Active
8 state changes, last state change 4w4d
Virtual IP address is 192.168.255.18
Active virtual MAC address is 0000.0c07.ac08
Local virtual MAC address is 0000.0c07.ac08 (v1 default)
Hello time 3 sec, hold time 10 sec
Next hello sent in 1.572 secs
Preemption enabled, delay min 60 secs, reload 60 secs, sync 60 secs
Active router is local
Standby router is unknown
Priority 100 (default 100)
Track interface FastEthernet1 state Up decrement 10
Group name is "GL-HSRP-OUT" (cfgd)
FastEthernet1 - Group 9
State is Active
11 state changes, last state change 4w4d
Virtual IP address is 192.168.98.205
Active virtual MAC address is 0000.0c0.ac09
Local virtual MAC address is 0000.0c07.ac09 (v1 default)
Hello time 3 sec, hold time 10 sec
Next hello sent in 1.572 secs
Preemption enabled, delay min 60 secs, reload 60 secs, sync 60 secs
Active router is local
Standby router is unknown
Priority 100 (default 100)
Track interface FastEthernet0 state Up decrement 10
Group name is "GL-HSRP-IN" (cfgd)
Router-R1#show standby brief
P indicates configured to preempt.
|
Interface Grp Pri P State Active Standby Virtual IP
Fa0 8 100 P Active local unknown 192.168.255.18
Fa1 9 100 P Active local unknown 192.168.98.205
Router-R1#

[Georg Pauwen]

Hello,

--> Standby router is unknown

What exactly is your question ? If this is a standalone router, HSRP won't work. What do you have connected to the router ?

[moon_blue69]

This is connected to a HA pair of 3750 but both ports are connected on to the same switch. As some one mentioned earlier this looks like some one hasn't completed the intended setup. I am trying to understand the setup.

[paul driver]

Hello @moon_blue69

the hrsp output confirms you don’t have any other hrsp peer. So basically this means hrsp isn’t resilient at this time.

[Richard Burts]

It is certainly not clear why there is configuration for HSRP here. But it is certainly clear that HSRP is not working here. It does no harm to have it in the configuration. But it does not achieve any benefit from having it.

HTH

Rick

[tonypearce1]

It looks like someone set up those HSRP IP addresses so they can monitor if the physical port goes down. For example, they can run a ping graph to 192.168.98.205 and this will fail / stop responding EDIT: will log a syslog message if the monitored interface "FastEthernet0" goes down. 

Same on the other interface.