Cisco 6504 E - not supporting VSS- need alternative solution for Redundancy

[ITexpert]

Hello Guys,

I am using Two Core switches 6504E with following modules ,

Module 1 : WS-SUP720-3B  - This has 1 gigabit ports

Module 2 : WS-X6704-10GE -->  This module does not support VSS with SUP720

Both core switches  are connected with each other by SFP Ports from Module 1: SUP720-3B.

Right now both switches have different IP addresses and firewall is just connected with core switch 1. 

I want to use both switches in redundant way so that both switches will act as a single switch because i want to serve intervlan routing in redundant way also.

Please provide suggestions ?

Also one question, Does all cisco switches have STP enabled by default ?

Thanks

[a.alekseev]

HSRP or VRRP + MSTP or RapidPVST+

[Troy Jackson]

You can add a switch between the firewall and the two core switches and then run HSRP between the cores. You will also need a trunk (L2 EtherChannel) between the two cores so you can run HSRP for your ingress SVIs. HSRP is not required but you will need a first hop redundancy protocol. 

I think most Cisco switches have some version of spanning-tree enabled by default.

[ITexpert]

Why i need to add new switch between firewall and core switches,  I just want to use Core switches in redundant way and then connect both switches with firewall.

STP is enabled by default on Firewall as well.

One more question , does 6504E support physical stacking ?

[Troy Jackson]

Sorry for the delay. The 6504E cannot be physically stacked. Which model firewall are you connecting too?

[ITexpert]

I am using FortiGate firewall.

[Troy Jackson]

I'm not familiar with the FortiGate. But I would look and see if they allow some type of layer2 bridging for their interfaces. If your goal is to make the two cores look like one logical core then you can only use HSRP or VRRP. You will need the links to be on the same subnet in order for the redundancy to work and that's why I mentioned the extra switch before.