What is the best approch to setup custom domain with static IP for AppEngine

Question

I had done an investigation on below

1. Adding custom domain through AppEngine settings - Doesn\'t seem to be static IP, it uses Google NS.
2. Setting up VM

Answer 1

Static IP for AppEngine/Cloud Functions can be achieved by HTTPS Load Balancer with "Serverless Network End Group" backend.

LB also helps multi-region serving for AppEngine and other serverless components.

This is similar to Internet NEG with HTTPS LB, serverless NEG can be mapped to Google internal services like Cloud run/CF, AppEngine. It was also possible to map multiple AppEngine services from the same GCP project.

I was able to gain early access to serverless NEG on my project and test on my side. I will update this post when Serverless NEG available for public access.

Edit (7/7/2020): Serverless NEG is available in Beta now and is available for everyone to access, See

Serverless network endpoint groups overview

Setting up serverless NEGs

Answer 2

As you can see at this documentation, "App Engine does not currently provide a way to map static IP addresses to an application. In order to optimize the network path between an end user and an App Engine application, end users on different ISPs or geographic locations might use different IP addresses to access the same App Engine application". So, there is no way to set a static IP address to App Engine but you can use a use a pool of IP address. In the shared link, you can find the way to use ranges of IP address in App Engine. This other link, explain a bit more how to do it.