Connenct two sites with same network address

[Rayes]

Hello Everyone,

I need help with the below scenario:

As shown in the attached image there's a two sites connected throw a Cisco ISR1004 we want to make a DR for site A in site B.

My questions is:

How to connect the both sites with same network address?

How can i keep site B connected to site A and reconnect it with Site A in DR site if site A fail?

[paul driver]

Hello
Can you elaborate what you mean on failure of site A, Do you mean if the mpls connection fails?
Adding redundancy to a network is a good thing however it can be expensive especially it involves adding an additional mpls interconnect, a cheaper solution could be to have raw internet feeds (RIF) at both sites and run something like an ipsec site-to-site vpn with OSPF over it which then can be used incase either site mpls link fails.

[Rayes]

Hello Paul,

What i mean by site failure is that all the site for some reason goes down and i has a replication solution that replicate all my virtual machines to site B and automatically start them up.

so what i want is when my virtual machines startup at site B with preserving same IP addresses they can not connect outside as no gateway exist in site B.

[Georg Pauwen]

Hello,

not sure I fully understand what you are trying to accomplish either, but why don't you just configure the DR machines with the duplicate IP addresses, shut down the link to the core switch, and activate that link (through a simple EEM script) when the MPLS link goes down ?

[Rayes]

Hello,

We have many clients which need to connect to the VMs with it's ip address. if we change the VM ip address we need to change all clients which will take forever.

So i need to preserver the vms which the same ip address when they startup at site B

[Georg Pauwen]

Hello,

that is exactly what I mean. You configure the same IP addresses on the backup devices, and only 'activate' them when the primary link goes down.

[Rayes]

As mentioned I have an existing Datacenter in site B which need to communicate with site A and i want to add servers to site B which will handle the Site A VMs when a failover occur.

My VMs will startup at site B but the gateway in site A is shut down

So how i can remain Site B to communicate with Site A in normal status and communicate with Site A vms in DR when a fail over occur.