cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
958
Views
5
Helpful
5
Replies

Catalyst 4500E High Availability Setup

avilt
Level 3
Level 3

I have few questions on the network design shown in the attachment.

1. Is this design correct, specially uplink connection between supervisor engines?

2. Let's say in Cascade-1, the top most L2 switch fails, then the traffic will go to Standby-L3 switch. In this case  the standby L3 switch will pass the traffic to Active L3 switch via uplink ports on Supervisor engine. Am I correct?

3. In case of complete breakdown of Active L3 switch, the connectivity to routers will be lost.(routers and L3 switches are running OSPF). I need to manually switch the router cables to the new active L3 switch. In this scenario how can I implement some kind of redundency to routers as well?

Thank You

1 Accepted Solution

Accepted Solutions

avilt wrote:

Thank You Jon.

Unfortunately I have only two interfaces on each router. Can I connect lan interface of  one router to active L3 switch and from another router to standby L3 switch. I am unable to find sample configuration/examples on Cisco website for this kind of setup.


If you only have 2 interfaces per router then yes you should connect one router to the active switch and one to the standby switch although i would stress again it is not really a standby switch.

The problem you have at the moment is that if the active switch goes you lose all your router connections.

As for sample configs, nothing special, just configure as you normally would using a dynamic routing protocol such as OSPF/EIGRP.  You can either have a shared vlan between the 2 switches and you have both routers interfaces in the same vlan or personally i would configure each router to switch connection as a P2P routed link.

Jon

View solution in original post

5 Replies 5

Leo Laohoo
Hall of Fame
Hall of Fame

Router going to one chassis instead of two.  So if the chassis/supervisor fails on the Active L3 ...

I need to manually switch the router cables to the new active L3 switch. In this scenario how can I implement some kind of redundency to routers as well?

Connect the redundant router to the redundant switch.  A 10Gb link, in red, should be more than enough to link both of them together.

Is there any sample configuration/example of this type of setup?

If I were to use just 2 L2 switch in each stack. do I need to define them in a cluster?

And if I were to use more than 2 L2 switches in a stack, do I need to create the cluster?

Thank You

avilt wrote:

Is there any sample configuration/example of this type of setup?

If I were to use just 2 L2 switch in each stack. do I need to define them in a cluster?

And if I were to use more than 2 L2 switches in a stack, do I need to create the cluster?

Thank You

You can simply interconnect each switch in the cascade although as i suggested in previous thread it would be better to connect each switch individually to both 4500 switches.

You don't need to define them as clusters.

Your 4500 connections to the routers are all wrong. Each router should connect to both 4500 switches. Try not think of what you call the "standby" 4500 as an actual standby. It is quite capable of passing traffic as much as the active switch and indeed it should be used as such otherwise you are wasting your network capacity.

Jon

Thank You Jon.

Unfortunately I have only two interfaces on each router. Can I connect lan interface of  one router to active L3 switch and from another router to standby L3 switch. I am unable to find sample configuration/examples on Cisco website for this kind of setup.

avilt wrote:

Thank You Jon.

Unfortunately I have only two interfaces on each router. Can I connect lan interface of  one router to active L3 switch and from another router to standby L3 switch. I am unable to find sample configuration/examples on Cisco website for this kind of setup.


If you only have 2 interfaces per router then yes you should connect one router to the active switch and one to the standby switch although i would stress again it is not really a standby switch.

The problem you have at the moment is that if the active switch goes you lose all your router connections.

As for sample configs, nothing special, just configure as you normally would using a dynamic routing protocol such as OSPF/EIGRP.  You can either have a shared vlan between the 2 switches and you have both routers interfaces in the same vlan or personally i would configure each router to switch connection as a P2P routed link.

Jon

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Innovations in Cisco Full Stack Observability - A new webinar from Cisco