Enterprise Soln: High Availability - VRRP / HSRP

 

VRRP:  Virtual Router Redundancy Protocol



Implementation Topology:  

Configurations;

Primary-Router:
Interface gi0/1
description LAN
vrrp 1 ip 10.1.1.254
vrrp 1 priority 110 
vrrp 1 track gi0/0 65   ///default is 10
vrrp 1 track 100 decrement 65    // Track internet

Track Internet Reachability:

R1(config)#ip sla monitor 10
R1(config-sla-monitor)#type echo protocol ipIcmpEcho 8.8.8.8
R1(config-sla-monitor-echo)#frequency 5
R1(config-sla-monitor-echo)#exit
R1(config)#ip sla monitor schedule 10 life forever start-time now
R1(config)#track  100 rtr 10

Secondary-Router:

interface gi0/1
description LAN-sec-gw
ip address 10.1.1.2 255.255.255.0
vrrp 1 ip 10.1.1.254
vrrp 1 priority 90     
vrrp 1 track 1 gi0/0 20


Note:
1) Default Priority is 100 (higher is better) ;
So you need to set the Secondary Router with a slightly lower Value
2) No need to set pre-empt, this is enabled by default in vrrp .

END.







standby/Active
Implementation:

Primary Router:

R1(config)#Interface gi0/1
R1(config)#description LAN   
R1(config)#ip address 10.1.1.1 255.255.255.0  
R1(config)#standby version 2 
R1(config)#standby 1 ip 10.1.1.254  
R1(config)#standby 1 priority 110  
R1(config)#standby 1 preempt  
R1(config)#standby 1 track gi0/0 65  
R1(config)#standby 1 track 100 decrement 65


 Track Internet Reachability:
R1(config)#ip sla monitor 10
R1(config-sla-monitor)#type echo protocol ipIcmpEcho 8.8.8.8
R1(config-sla-monitor-echo)#frequency 5
R1(config-sla-monitor-echo)#exit
R1(config)#ip sla monitor schedule 10 life forever start-time now
R1(config)#track  100 rtr 10

Secondary Router:

R2(config)#interface gi0/1
R2(config)#description LAN-sec-gw
R2(config)#ip address 10.1.1.2 255.255.255.0
R2(config)#standby 1 ip 10.1.1.254
R2(config)#standby 1 priority 90
R2(config)#standby version 2
R2(config)#standby 1 preempt
R2(config)#standby 1 track  gi0/0 20



1) Default Priority is 100 (higher is better) ;
So you need to set the Secondary Router with a slightly lower Value

2) Preempt needs to be set only if you want the active router to
take back the role once a failover as occurred.


Troubleshooting:



R2(config-if)#do show standby
FastEthernet0/0 - Group 1 (version 2)
  State is Standby
    4 state changes, last state change 00:03:04
  Virtual IP address is 10.1.1.254
  Active virtual MAC address is 0000.0c9f.f001
    Local virtual MAC address is 0000.0c9f.f001 (v2 default)
  Hello time 3 sec, hold time 10 sec
    Next hello sent in 1.208 secs
  Preemption enabled
  Active router is 10.1.1.1, priority 110 (expires in 9.096 sec)
  Standby router is local
  Priority 90 (configured 90)
    Track interface GigabitEthernet2/0 state Up decrement 20
  IP redundancy name is "hsrp-Fa0/0-1" (default)


R1#show standby
FastEthernet0/0 - Group 1 (version 2)
  State is Active
    2 state changes, last state change 00:50:56
  Virtual IP address is 10.1.1.254
  Active virtual MAC address is 0000.0c9f.f001
    Local virtual MAC address is 0000.0c9f.f001 (v2 default)
  Hello time 3 sec, hold time 10 sec
    Next hello sent in 2.300 secs
  Preemption enabled
  Active router is local
  Standby router is 10.1.1.2, priority 90 (expires in 8.440 sec)
  Priority 110 (configured 110)
    Track interface GigabitEthernet3/0 state Up decrement 65
    Track object 200 state Up decrement 65
  IP redundancy name is "hsrp-Fa0/0-1" (default) 

 
End.