/56 vs /64 IPv6 block on Linode
I recently got a /56 IP block from Linode. Upon calculating the block size, I got this range: aaaa:bbbb:cccc:700::/56 to aaaa:bbbb:cccc:7ff:ffff:ffff:ffff:ffff/56. However, upon verifying it with the support people, they said that it was actually up to ...:700:ffff:ffff:ffff:ffff instead of ...:7ff:ffff:ffff:ffff:ffff. Why is this, and how many /64 blocks does it contain? Am I still able to use, let's say, aaaa:bbbb:cccc:7aa:f:f:f:f? Thanks so much!!
2 Replies
The range of a /56 is indeed aaaa:bbbb:cccc:700:: through aaaa:bbbb:cccc:7ff:ffff:ffff:ffff:ffff. A /56 contains 2^(64-56) = 256 /64s. You can use anything in the /56. The support person must have been mistaken.
I see, thanks!!