@Ngranade 

Hi Nahuel,

It's unfortunate that you're experiencing difficulties reaching the gateways from both your ER605 router and Cisco 861 router, despite the VPN tunnel appearing to be correctly set up. To troubleshoot this issue, I suggest checking the following:

1. Static Routes: Ensure that you have configured the necessary static routes on both routers to allow proper routing between the two networks.

2. NAT Configuration: Double-check the  bitcoin NAT configuration on the ER605 router to ensure that it is properly set up and not causing any issues with the VPN tunnel.

3. Firewall Settings: Review the firewall settings on both routers to make sure they are not blocking any necessary traffic.

4. VPN Configuration: Verify that the VPN settings, such as encryption algorithms and pre-shared keys, are correctly configured on both routers and match each other.

If you have already checked these configurations and are still unable to reach the gateways, I recommend reaching out to the technical support team of both the ER605 and Cisco 861 routers. They can provide further guidance and assistance specific to your setup.