Right now, when you create an app you get a dedicated IPv4 address. Your 8 apps would have 8 IPs unless you removed them (using flyctl ips ).
What would be the consequence of removing the IP? Like I CNAME example.com → example.fly.dev. I assume currently that example.fly.dev in turn resolves to the IP. Would it just stop working?
Meaning an app has to have an IP assigned? And if so, the only way to avoid that $4 per app (since, per IP) additional charge would be to wait for shared IPs? In which case I assume removing the dedicated IP would revert to a shared IP.
I moved this to a new topic because it’s interesting information.
Right now, we don’t adjust the DNS entry for <app>.fly.dev when you add or remove IPs, it’s always pointed at the first two IPs we provision. That’s something we plan to change. If you remove your ipv4, <app>.fly.dev will only work for ipv6 lookups at that point.
When we ship shared IPs, you’ll be able to add a shared IP to your app just like a normal ipv4.