Why No-NAT rule is required to communicate between On-Prem to VPC (in GCP)

[ballu]

Hi,

In GCP we have our own VPC where we have Checkpoint in cluster state. There is a connectivity with our On-Prem environment via VPN on Direct connect.

While Communicating the resources behind the Checkpoint gateway from On-Prem we need to configure a No-NAT rule for it work. 

Why do we require a No-NAT rule in this scenario? 

Thanks,

Baljinder Singh Bimbh  

[Chris_Atkinson]

The obvious guess would be that your NAT policy isn't specific enough in other areas but is a little difficult to say without knowing the exact composition of the policy.

The other could be the implied inclusion of the Gateway address in the encryption domain could be causing a challenge.

[the_rock]

I think if you sent us basic diagram with explanation of traffic flowing, it would certainly help.

Andy