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Google Cloud Platform Reserved Address Space in VPC Network Route

I need to add a route in GCP's VPC Network and when I do, I get an error (shown below) that appears to state there is an overlap/conflict with the 10.130.0.0/16 range. I unfortunately do not see this 10.130.0.0/16 in any route, in any region and I have no idea why this error is occurring.

Creating route "test" failed. Error: Invalid value for field 'resource.destRange': '10.130.90.82/32'. 10.130.90.82/32 hides the reserved address space for network (10.130.0.0/16).

I have tried adding this simple route in several gcp projects but they all fail and seem to imply there might be some hidden reserved address space. Could this be? What am I missing? This occurs with any route destination value that is in the 10.130.0.0/16 space eg; 10.130.90.82/32 10.130.90.0/24

For clarification here is an example Route that fails: enter image description here

Additional Clarification, Here is the 'default' VPC Network: enter image description here

Solution

  • There is in fact a hidden reserved address space in the default VPC network. I hesitate calling hidden as JaysonM mentioned it in his answer but it does not appear anywhere in the GPC console (to my knowledge).

    The default VPC network is using 'auto' subnet creation mode. With this setting enabled the VPC network has a range of 10.128.0.0/9 (10.128.0.0 - 10.255.255.255) that cannot be overlapped. Simply setting 'auto' subnet creation of the VPC network to 'custom' will resolve this issue. Do also note this is a one-way change for your VPC network.

    Cheers!