On Sun, Nov 28, 2021 at 1:18 PM Karl Auer <kauer@biplane.com.au> wrote:
On Sun, 2021-11-28 at 12:53 -0800, Michael Thomas wrote:
I was reading their howto yesterday and it seems they are only allocating a /64? Why?
That's a /64 *per subnet*...
But the size of a VPC's IPv6 CIDR block does seem to be fixed at /56. Would have been nice to see /48 instead.
Hi Karl, To what purpose? You can't alter the VPC routing of any of the IP addresses (v4 or v6) assigned to an AWS VPC. If you try, for example, to assign a /64 to an instance you get a funky error: "Route destination doesn't match any subnet CIDR blocks." You can only assign the block's IP addresses to subnets or not and then assign addresses from the subnet to the instances. You can't have more than 256 subnets in a VPC so why would you need more than a /56 of IPv6 addresses? Regards, Bill Herrin -- William Herrin bill@herrin.us https://bill.herrin.us/