How to turn traffic from one tunnel to another?

Question

Mikrotik

Good day! Data center situation three offices in tiki offices in the CENTOS data center are all connected by GRE tunnels. In one of the offices, the provider said I would mess up, in general, how to get to the data center from office 3 through office 2

Answer 1

Nikita Reshetnyak ,

how can I get to the data center through the tunnel from 3 to the second office

Now you can answer like this: route the traffic of office 3, heading to the data center, through office 2.
Total:

• In office 3, add routes to data centers IP through GRE tunnel to office 2
  
• In office 2, host (disguise) traffic with the source "office 3" and the direction "Data Center"