Regarding Failover between Leased line and VPN

[Janardhan Meesala]

Dear Experts!!!!!!!!

I am going to design one network. I had queries with this design.

Let me explain scenario first( it was attached below).

I have two sites, Site-A and Site-B, repectively.

In site-A i have one Cisco 1841 router, one Cisco ASA 5510 firewall and One cisco 3560 layer 3 switch.

in site-B i have one Cisco 1841 router, one Cisco ASA 5505 firewall and One Cisco 3560 layer 3 switch.

From ISP side

I have point-to-point leased line between sites A and B. And both sites have internet connectivity from another ISP.

I planned to terminate leased line in cisco 1841 router in both branches for branch to branch connectivity.

I will configure site to site VPN between two sites, A and B.

Here my query was i want make VPN as failover connectivity if leased line fails. In both the cases, i need internet to the inside users in both sides.

Please give me suggestions to configure this requirement.

Summary requirement:

Leased line is Primary and VPN is Back-up, if leased line fails. In both cases internet is needed to inside users.

I am attaching design diagram below.

Regards,

MJR

[prasad.gsmc · Accepted solution]

Hi,

I am giving you some suggestion based on the following assumption

Both Site the traffic pertaining to Remote site will come to the router.

The best way to achieve your requirement is to do GRE over IPSec

Step 1: Conigure a gre tunnel between two sites over Internet

Step 2: Protect GRE End points using IPsec

Step 3: Ensure proper route failover between sites either by running Routing protocols between GRE as well as Leased line

The GRE tunnel destination should be routed through Firewall, ie on each router add a route to reach the IPSec ./ GRE end point

refer the design guide

http://www.cisco.com/en/US/tech/tk583/tk372/technologies_configuration_example09186a00800a43f6.shtml

regards

Prasad

[Janardhan Meesala]

Dear Prasad,

I very new to this GRE tunnel.

Will you brief me how GRE tunnel will work???

As per my scenario i need to use leased line as primary and VPN as back-up connection for site to site connectivity.

then how to achieve this????

Is there any chance to configure Load balancing?????

Regards,

Janardhan

[Janardhan Meesala]

HI Prasad,

I gone through the link what you given.

In that one default route was configured towards firewall.

In my scenario i need to configure two default routes, one is pointing towards Leased line and another one pointing towards Firewall. Then how packet takes priority towards leased line over Firewall side.

Regards,

Janardhan