HSRP not working in Cisco 3650

[pritamjitbiswas]

Hi everyone.

i have a existing cisco 3650. all the vlan is configure there and this switch is connected to firewall for internet access.

i parches a new 3650 and configure HSRP for redundancy. the old switch is working fine but after configuring the HSRP in new switch my network goes down. the old switch keep electing as active to speak to standby in a never ending loop. all though i have set higher priority to old switch but as soon as i connect the new switch in the network it keep electing as active to speak to standby in a never ending loop can any one help me with this issue. and also in stand alone mode the switch is unable connect the inter net all thou i have created a default route to my firewall. i have attach the running configuration and standby result for reference.

thnx for you help

[balaji.bandi]

Do you have any high level diagram how these switches connected each other - and FW connected too.

[pritamjitbiswas]

this is the physical diagram

[Giuseppe Larosa]

Hello @pritamjitbiswas ,

you need a L2 trunk between the two switches carrying all the Vlans where you want activate HSRP.

The best way to implement this is using a L2 port channel using LACP to have redundancy and increased bandwidth.

I have seen in the configuration files  that there are  no inbound ACLs applied to SVI interfaces, so there is no ACL that can drop HSRP hello messages. This is good.

Hope to help

Giuseppe

[paul driver]

Hello

Is it due to the physcial location of those two switches as to why you just havent stacked them into one logical device instead of using them individually and running HSRP between them?

[Vick28719]

I hope these are your lab routers, otherwise suggest changing your password and encrypting them for future. 

Next i dont see trunks between the 2 switches to pass all the vlan. Remove preempt on the secondary switch. 

When you activate HSRP on both side, they need to see the multicast hello packets on both ends, else they will fail to establish HSRP relationship and will keep bouncing between active/listener state. 

For the internet to be down when you enable HSRP, what is the return route from FW pointing to ? 

[pritamjitbiswas]

HI every one. thanx for your reply . i have one question if there is any problem in the configuration how only vlan 5,30,160,170,180 working fine as it should be but other vlan not working .

[Giuseppe Larosa · Accepted solution]

Hello @pritamjitbiswas ,

seeing your network diagram the two C3650 do not have a direct L2 trunk between them .

So in order to verify what is happening you need to verify the three C2960 in the middle.

if you are using VTP you can have the two C3650 as VTP servers and the other as VTP client.

If all devices are in VTP transparent mode  you need to configure manually all the Vlans on each of the switches.

All the switches must agree on the set of defined VLANs to have a working solution.

use

show vlan

to compare the vlan database on each switch

use

show vtp status

to check the VTP status of each switch.  if using VTP all switch must agree on the same revision number and on the identity of the last updater (an IP address)

Hope to help

Giuseppe