How to only assign ipv6 address?

Documentation says that ipv6 are free and ipv4 are billable.

How do I assign only ipv6 address?

If you have flyctl installed you can use this command :

flyctl ips allocate-v6 --app <your_app>

It will only assign an ipv6 address. You need to do the same command, and replace the 6 with a 4 to assign an ipv4 address.

If I check existing apps, it seems like they are assigned ipv4 by default. I cannot find how to configure fly not to do that.

Your app doesn’t have an ipv4 assigned by default.

And the first ipv4 is free.

I don’t know what you are looking, but mine definitely do.

Regardless. While it might be free, I am looking for ways how to optimize app load time. I would think that reducing the requirement for ipv4 could help.

My app, my db, and my builder. They all have no ipv4/ipv6 by default.

I check mine using:

query ($name: String!) {
  app(name: $name) {
    state,
    status
    ipAddresses {
      nodes {
        address
        type
      }
    }
  }
}

and they def do.

Their spec does not mention anything about ipv4/ipv6

Will need to wait for someone from their team to follow up