HSRP

[lobo66]

I have HSRP configured on two 3845's one with a priority of 110 one with 100, any reason both routers show a state of
'Active'

THX all

 

[ADB100]

It's not working..............

Seriously though the routers must have layer-2 connectivity between each other (i.e. plugged into the same switch and on the same VLAN). It could be incorrect config however; post your HSRP config from the 2 routers. The one with the 110 priority should be active and the other standby.

HTH

Andy

 

[lobo66]

router1
interface FastEthernet1/0
description XYZ Dev Network
no switchport
ip address 10.247.19.70 255.255.255.192
ip nat outside
ip virtual-reassembly
duplex full
speed 100
standby ip 10.247.19.68
standby preempt

router 2
interface FastEthernet1/0
description ISE Dev Network 209.140.121.64/27
no switchport
ip address 10.247.19.69 255.255.255.192
ip nat outside
ip virtual-reassembly
duplex full
speed 100
standby ip 10.247.19.68
standby priority 110
standby preempt

 

[ADB100]

As long as they are on the same Layer-2 network that should work. I would put a cross-over cable between the 2 Ethernet interfaces to eliminate any switch issues.

HTH

Andy

 

[UnaBomber]

Why do you have ip nat outside on an interface you want to implement hsrp? I am not saying it cant be done, but why would you have hsrp on the "outside" of your network?

UnaBomber
ccnp mcse2k

 

[ADB100]

Why do you have ip nat outside on an interface you want to implement hsrp? I am not saying it cant be done, but why would you have hsrp on the "outside" of your network?

NAT & HSRP on the outside interface are reasonably common between customers hand-off routers and the Service provider when no dynamic routing protocol is used. i.e. the SP has a single next-hop configured for the customers IP network/subnet. What is also generally configured in this scenario is the reverse as well where the SP has 2 routers running HSRP and the customer has a single next-hop for the default route.
With it configured like this both the customer and SP have hardware redundancy without having to run a dynamic routing protocol between each other.

I am not saying this is the correct way of doing it but this is quite common.

 

[UnaBomber]

yes I see what you mean. I havent ever seen something like that in production tho. IMHO You could have a lot of different types of problems in that scenario which could take a lot of time to troubleshoot and resolve.

Alternatively he could have his NAT back to front, there is sometimes reasons to do this also, ie so both sides can hide there systems from each other.

Its just not common to see a config like that, thats why I asked.

UnaBomber
ccnp mcse2k

 

[lobo66]

Thanks for all the input think we go t a little side tracked on the general question of HSRP but I solved it, removed the HSRP and reapplied it, pretty weasy fix .. As for the NAT it a router in a DMZ for an exteranl connection, and it is a very common practice in this type of environment.