Re:External IPv6 addresses for VM instances is now in Genera...
by Clewza313 on Wednesday July 28, 2021 @09:54AM
(#27983762)
Private addresses are free, so there's no cost to keeping them.
Re:External IPv6 addresses for VM instances is now in Genera...
by knorker on Wednesday July 28, 2021 @01:11PM
(#27986231)
Simplicity, for one. One set of routing tables, firewall rules, etc.
And if you don't have any IPv4 then you know that you are not accidentally falling back to IPv4.
For single-VM it doesn't matter, because who would you talk to, but if you have a bigger cloud setup then it would be nice to remove IPv4.
So depends what you mean by "cost".
It looks like there's currently no way to go literally v6-only, i.e. not even having a private v4 address on the VM. The instance metadata server as well as the default DNS and NTP servers are still v4-only.