HSRP with 2 x 877 routers and Cisco switch

[Pawel Lenart]

Hi, I'm trying to setup HSRP on two C877 routers. Fo some reason advertisements / helo packets are not going from one router to the other. I have Cisco switch (C2960) in between and I was wondering If I need to set up something on this switch?

My configuration:

R1:

interface Vlan1

ip address 192.168.10.254 255.255.255.0

ip access-group V1-IN in

ip nat inside

ip virtual-reassembly

ip tcp adjust-mss 1452

standby delay minimum 10 reload 120

standby version 2

standby 1 ip 192.168.10.250

standby 1 timers 5 15

standby 1 priority 10

standby 1 preempt delay minimum 5 reload 30 sync 10

standby 1 name GROUP1

standby 1 track ATM0

R2:

interface Vlan1

ip address 192.168.10.253 255.255.255.0

ip access-group V1-IN in

ip nat inside

ip virtual-reassembly in

ip tcp adjust-mss 1452

standby delay minimum 10 reload 120

standby version 2

standby 1 ip 192.168.10.250

standby 1 timers 5 15

standby 1 priority 5

standby 1 preempt delay minimum 5 reload 30 sync 10

standby 1 name GROUP1

standby 1 track 1 decrement 10

Switch:

interface Vlan1

ip address 192.168.10.234 255.255.255.0

no ip route-cache

Debug: (debug standby pack all)

R1:

Jun 25 11:57:14.589: HSRP: Vl1 Grp 1 Hello  out 192.168.10.254 Active  pri 10 vIP 192.168.10.250

Jun 25 11:57:19.330: HSRP: Vl1 Grp 1 Hello  out 192.168.10.254 Active  pri 10 vIP 192.168.10.250

Jun 25 11:57:24.079: HSRP: Vl1 Grp 1 Hello  out 192.168.10.254 Active  pri 10 vIP 192.168.10.250

Jun 25 11:57:28.407: HSRP: Vl1 Grp 1 Hello  out 192.168.10.254 Active  pri 10 vIP 192.168.10.250

Jun 25 11:57:33.176: HSRP: Vl1 Grp 1 Hello  out 192.168.10.254 Active  pri 10 vIP 192.168.10.250

Jun 25 11:57:37.336: HSRP: Vl1 Grp 1 Hello  out 192.168.10.254 Active  pri 10 vIP 192.168.10.250

R2:

Jun 25 11:58:11.536: HSRP: Vl1 Grp 1 Hello  out 192.168.10.253 Active  pri 5 vIP 192.168.10.250

Jun 25 11:58:15.893: HSRP: Vl1 Grp 1 Hello  out 192.168.10.253 Active  pri 5 vIP 192.168.10.250

Jun 25 11:58:20.602: HSRP: Vl1 Grp 1 Hello  out 192.168.10.253 Active  pri 5 vIP 192.168.10.250

Jun 25 11:58:25.230: HSRP: Vl1 Grp 1 Hello  out 192.168.10.253 Active  pri 5 vIP 192.168.10.250

I can communicate between both routers (using ping or ssh) and CDP is showing neighbours correctly.

Any idea why it's not working correctly?

[Giuseppe Larosa]

Hello Pawel,

in order to have the two routers to exchange HSRP hello packets the switch has to work at OSI layer2 not OSI layer3 as a router for vlan1.

Try after having shutdown SVI vlan1 on the LAN switch C2960, in this way the C2960 will act as an OSI L2 switch.

Edit:

Karsten is on spot here look at the ACL applied inbound

Hope to help

Giuseppe

[Karsten Iwen · Accepted solution]

You have access-lists on your VLANs. Are you allowing the HSRP-Packets there? HSRPv2 uses the destination-address 224.0.0.102 (instead of 224.0.0.2 which was used by HSRPv1) with port 1985.

[Pawel Lenart]

ACL was blocking it. Manage to solve this problem. Thanks guys for your help.