Routing ussue between two sites using the same IP address

[Steev112]

Hi,

I have MPLS cloud, between PE and CE is BGP, one customer has two data centers, each data center has main frame on active in customer-A and other is standby in customer-B that main the interface shutdown, both main frame has the same IP address 10.10.10.10.

From CE and Firewall point to point, and configure static route for this subnet 10.10.0.0/16 on CE-A and redistribute into BGP, and any branches want to access main frame go to Customer-A,

My question, if the active main frame went down how the standby one will be active:

1. Shall I configure static route for big subnet 10.10.0.0/16 on Customer-B CE and increase the administrative distance to 200 and only I need to shutdown the interface.
2. Or configure IP SLA on CP-B to track the active main frame.

I am confusing to achieve this scenario if anyone can help me to do it in easy way.

The scenario in attached file

[Markus Benz]

Hi Steven,

is your Mainframe able to do OSPF.
If yes, I would recommend to run OSPF on it and inject routes of the active LPAR's.
(I don't know your main frame setup, maybe this is useless)

So Manframe A has IP A and Manframe B has IP B. The use these IP addresses to talk OSPF to the network and the active one is announcing IP address C to the network. IP address C would be the one clients connect to.

Would that be possible with your Mainframes?

Regards,
Markus

[Steev112]

Hi Markus,

I don't  have an access on main frame, but i can reach this subnet from CPE by adding static route and reditribute into BGP, customer want to use the same main frame IP address in another place as standby, what i am thinking to add static router there but i will increase the administrative distance once they shutdown the main main frame and and no shutdown for standby, the users will be able the mail frame.

I don't know if the scenario Ok or there is another solution.

Thanks

[Markus Benz]

From my point of view it would be best if you could provide a dynamic way to the main frame owners to switch sites.
One common way is to enable OSPF between the Main Frame and  the network, so that they can inject the active IP addresses (host routes) via OSPF. From network point of view this is all dynamic and does not require any steps on the network to switch over.

If you do not have the possibility to configure a routing protocol to the MF and you need to use static routes that's fine as well, but it will require manual configuration changes to switch over to the other site.

What you could test is a tracking object for the static routes. Like pinging the next hop for example. To give you a configuration or an exact example I would need to have more details around the MF implementation. How many IP's you have there and how routing is done etc.

Regards,
Markus