Need to use same IP on two interfaces

[agarwalgaurav3344@gmail.com]

Hello,
I want to use same subnet IP on two interfaces of same router, to connect Firewall in HA under edge device. I need 2 connections from each router to each firewall.
below is by configuration
R1
G0/0: ISP A IP
G0/1: 172.16.1.2/23
R2
G0/0: ISP B IP
G0/1: 172.16.1.3/23
on G0/0: BGP is there 
on G0/1: GLBP is configured to make redundancy in both router LAN 
Default Routing is also configured in case if ISP went down
now I need to configure interface G0/2 in the same subnet so I can add both firewall with both routers.

[MHM Cisco World]

Use BVI 

https://www.cisco.com/c/en/us/support/docs/lan-switching/integrated-routing-bridging-irb/200650-Understanding-Bridge-Virtual-Interface.html

MHM

[agarwalgaurav3344@gmail.com]

Hello,
ieee protocol is not available please suggest which one can I use from below. 

Royter Model : C8300-1N1S-4T2X 

[MHM Cisco World · Accepted solution]

If not support ieee then other solution is add SW between two FW HA and routers'

In SW add two vlan one for each edge router

MHM

[bbb bbb · Accepted solution]

Dear agarwalgaurav3344@gmail.com ,

How about use a switch between the router and FW. because router will not allow to add an IP address of the same subnet of another interface on the same router. The switch may also provide additional flexibility if in case you want to add few more devices on the same subnet (and using VLANs for other subnet). 

Let us know how we can help.

pls rate helpful post.

happy to help

best regards, 

[agarwalgaurav3344@gmail.com]

Hi,

Let me try to put a switch in between if it works, I will let you know.

[agarwalgaurav3344@gmail.com]

Hi,

It is working good after putting a switch between a firewall and router.

[bbb bbb]

Dear agarwalgaurav3344@gmail.com 

That is great! If you don not mind, may I know if the switch implemented as stacked switch or in HA? or just a single switch between the router and fw...

best regards

[agarwalgaurav3344@gmail.com]

Hi,

I simply put a non-managed switch between router and firewall.