I'm new to IPv6 and having some issues with a configuration that was really easy/common with IPv4.
My setup looks like this:
WAN (ISP managed router) <-> Router 1 ( my internal router ) <-> My workstations/devices
With IPv4 I would assign private IPs for my workstations/Router 1 (Eg.: in subnet 192.168.0.0/24), Router 1 would also have another private IP with my ISP Router in another subnet ( Eg.: 192.168.100.0/24 ) and with NAT everything would work normally.
Now, with IPv6, the ISP router receives and advertise a /64 IPv6 block. I was able to use dhcp6 client in Router 1 to receive the prefix and then use IPv6 autoconf to allow my workstations to get their IPv6 from that /64 block.
Internally, workstations can ping each other and Router 1, but they can't access the internet.
After contacting my ISP, I was informed that with a /64 block I would only be able to use IPv6 if my workstations were connected directly to the ISP router. And, to make my setup work, I would need another /64 block. Is it true? If so, why? ( their support couldn't explain the reason )
Aren't there another alternatives in this case?