HSRP behaviour

Unanswered Question
Sep 2nd, 2009

HSRP behaviour

Hi experts! I have an HSRP configuration between PC-Linux and 2 routers, and this is the configuration:

ROUTER-1

interface Vlan10

ip address 200.25.192.18 255.255.255.224

standby 110 ip 200.25.192.17

standby 110 timers msec 300 1

standby 110 preempt

ROUTER-2

interface Vlan10

ip address 200.25.192.19 255.255.255.224

standby 110 ip 200.25.192.17

standby 110 timers msec 300 1

standby 110 priority 200

standby 110 preempt

Hi experts! I have an HSRP configuration between PC-Linux and 2 routers, and this is the configuration:

ROUTER-1

interface Vlan10

ip address 200.25.192.18 255.255.255.224

standby 110 ip 200.25.192.17

standby 110 timers msec 300 1

standby 110 preempt

ROUTER-2

interface Vlan10

ip address 200.25.192.19 255.255.255.224

standby 110 ip 200.25.192.17

standby 110 timers msec 300 1

standby 110 priority 200

standby 110 preempt

So, ROUTER-2 is "active" and ROUTER-1 is "standby". Also, I have a Port Channel between these 2 routers. In normal conditions everything is working fine:

- ROUTER1 is power-on, ROUTER2 link is power-on, the traffic is going through ROUTER2.

- ROUTER1 is power-OFF, ROUTER2 is power-on, the traffic is going through ROUTER2.

- ROUTER1 is power-on, ROUTER2 is power-OFF, the traffic is going through ROUTER1.

But I am not sure about the behaviour when the router is power-on but it has a 100% of CPU Process. Normally, the HSRP is verifying the interfaces and when the process is high the interfaces are still up. I have some doubts about HSRP:

1.- When ROUTER2 (active) is with 100% CPU Process, does the traffic must siwtch to ROUTER1?

2.- Does PC-Linux know if ROUTER2 is totally down even when it has 100% CPU Process?

3.- Does HSRP work if the router is power-off of it has a 100% process?

Thanks guys!

Saludos,

Carlos*

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
Jerry Ye Wed, 09/02/2009 - 16:56

1. The answer is it depends. If ROUTER2 loses its heartbeat (HSRP HELLO) with ROUTER1 due to high CPU, then ROUTER1 will take over. If heartbeat still present, then ROUTER1 will not take over.

2. PC-Linux will not know ROUTER2 is down or not. Since HSRP uses virtual MAC address, and when ROUTER1 takes over, it will take over the virtual MAC also.

3. Do not understand your question.

HTH,

jerry

Actions

This Discussion