hsrp

arsalan921

hello everyone

i would like to ask one question regarding hsrp.
2 routers connected to a switch. they are connected to each other also.
R1's 1 interface to switch, 2nd interface to R2.
R2's 1 interface to switch, 2nd interface to R1.
R1 is primary for vlan 2 and secondary for vlan 3
R2 is primary for vlan 3 and secondary for vlan 2

doing it in gns3.

here is configuration, please see it...

==========================================================

on ROUTER1

---

hostname R1

vlan database
vlan 2
vlan 3
apply

int fa 1/0 ( connected to switch)
switchport mode trunk

int fa 1/2 ( connected to router )
switchport mode trunk

interface vlan 2
ip address 192.168.2.5 255.255.255.0
standby 1 ip 192.168.2.254
standby 1 priority 200
standby 1 preempt
standby 1 track fast 1/0

interface vlan 3
ip address 192.168.3.6 255.255.255.0
standby 2 ip 192.168.3.254
standby 2 priority 190
standby 2 preempt
standby 2 track fast 1/0


on ROUTER2

---

hostname R2

vlan database
vlan 2
vlan 3
apply

int fa 1/0 ( connected to switch)
switchport mode trunk

int fa 1/2 ( connected to router)
switchport mode trunk

interface vlan 2
ip address 192.168.2.6 255.255.255.0
standby 1 ip 192.168.2.254
standby 1 priority 190
standby 1 preempt
standby 1 track fast 1/0

interface vlan 3
ip address 192.168.3.5 255.255.255.0
standby 2 ip 192.168.3.254
standby 2 priority 200
standby 2 preempt
standby 2 track fast 1/0

==========================================================
is this configuration right ?

thank you

stuh84

Not quite. The default track value decrement is 10, so even if Fa1/0 goes down on the router, the standby wont take over as active. Configure a bigger decrement, or do the difference between the priorities as less than 10.

arsalan921

thank you for your reply

i have done the change.

priority value difference set to 5.

200 and 195

techED

Only use the preempt for the primary routers and the secondary routers no preempt (lower priority).


ROUTER1

---

interface vlan 2
ip address 192.168.2.5 255.255.255.0
standby 1 ip 192.168.2.254
standby 1 priority 200
standby 1 preempt
standby 1 track fast 1/0

interface vlan 3
ip address 192.168.3.6 255.255.255.0
standby 2 ip 192.168.3.254
standby 2 priority 190
standby 2 track fast 1/0


ROUTER2

---

interface vlan 2
ip address 192.168.2.6 255.255.255.0
standby 1 ip 192.168.2.254
standby 1 priority 190
standby 1 track fast 1/0

interface vlan 3
ip address 192.168.3.5 255.255.255.0
standby 2 ip 192.168.3.254
standby 2 priority 200
standby 2 preempt
standby 2 track fast 1/0

networker050184

techED wrote: »

Only use the preempt for the primary routers and the secondary routers no preempt (lower priority).

You still need preempt on the standby so it can take over if the priority falls below on the active in the case of a track lowered priority.

stuh84

I add to it that you should have preempt on both sides, but with the wait/reload timers invoked, that way any traffic isn't going to get blackholed while the network reconverges after a power failure and/or reload on a router. This would stop the reloaded router taking over as primary until a certain amount of time after.