VPN Tunnel Routing

[Charger1129]

Hi. I was wondering how I can go about routing traffic from 1 VPN tunnel to another. For example:

Site A

1. Subnet: 10.1.1.10

Site B

1. Subnet: 10.1.1.20

Site C

1. Subnet: 10.1.1.30

If I have point A as my main middle location, and point B and C as my spoke locations with VPN tunnels going back to site A, how can I configure it so that traffic in site B can reach site C by first passing through site A?

[Dinesh Moudgil]

Hi Charger1129,

Here are the crypto access-list and nat exemption configuration that you need:-

On site A for tunnel to Site B
1. crypto acl from A to B as
permit 10.1.1.10 to 10.1.1.20------from Site A to Site B
permit 10.1.1.30 to 10.1.1.20------from Site C to Site B

Nat exempt
From 10.1.1.10 to 10.1.1.20
From 10.1.1.30 to 10.1.1.20

On site A for tunnel to Site C
1. crypto acl from A to C as
permit 10.1.1.10 to 10.1.1.30------from Site A to Site C
permit 10.1.1.20 to 10.1.1.30------from Site B to Site C

Nat exempt
From 10.1.1.10 to 10.1.1.30
From 10.1.1.20 to 10.1.1.30

On site B for tunnel to Site A
1. crypto acl from B to A as
permit 10.1.1.20 to 10.1.1.10----- from Site B to Site A
permit 10.1.1.20 to 10.1.1.30------from Site B to Site C

Nat exempt
From 10.1.1.20 to 10.1.1.10
From 10.1.1.20 to 10.1.1.30

On site C for tunnel to Site A
1. crypto acl from C to A as
permit 10.1.1.30 to 10.1.1.10---- from Site C to Site A
permit 10.1.1.30 to 10.1.1.20---- from Site C to Site B

Nat exempt
From 10.1.1.30 to 10.1.1.10
From 10.1.1.30 to 10.1.1.20

Regards,
Dinesh Moudgil

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