IPSec VPN Between 3 sites, but i can made modifications in only device

RouterOS General
1

Hi!
I have a situation similar to the one described in this topic: http://forum.mikrotik.com/t/ipsec-vpn-between-3-sites/125401/1

I have a tree sites: A, B and C. (192.168.1/24 , 192.168.2/24, 192.168.3/24). And i have IPSEC Tunnels, works correctly: A ↔ B / B<->C.
I need devices from the site A access devices to site B (temporaly). I’m not worried about performance right now, there are few packages trafficked and it’s a temporary situation.

The solutions described in the topic involved making modifications to the 3 routers. But, i have access only site B.

Is there any alternatvie (for example, virtual IPs, nat) to implement this communication?

Thanks a lot!

2

I guess you mean from A to C (A to B would simply use the tunnel you have). And yes, NAT can help you. If you want 192.168.1.x connect to 192.168.3.y, then connect to 192.168.2.z instead (it’s best if it’s some free unused address) and on B do:

/ip firewall nat
add chain=dstnat src-address=192.168.1.x dst-address=192.168.2.z action=dst-nat to-addresses=192.168.3.y
add chain=srcnat src-address=192.168.1.x dst-address=192.168.3.y action=src-nat to-addresses=192.168.2.z