3 ms·

fc00::/7 is the space for that private range, it's as routable and subnettable as 10.0.0.0/8

• cesarb 5y ago
  > fc00::/7 is the space for that private range A small nitpick: the lower part of that range is reserved for future expansion, so the private range is actually fd00::/8. And you should pick a random /48 within that to be your private 10.x.x.x-like range, not use the whole /8. (See https://en.wikipedia.org/wiki/Unique_local_address#Definition https://en.wikipedia.org/wiki/Unique_local_address#Definitio... for more details.)
  • smitty1e 5y ago
    Ecxellent. Learned somthing imprtant today. As long as there is a provision to soak it in CIDR. I had looked at the dual-stack portion of AWS some years ago and did not see how this worked. Doubtless, my oversight.
    • eqvinox 5y ago
      > As long as there is a provision to soak it in CIDR. There is; the idea is to fill up random bits to /48, leaving you with 16 bits of subnetting space until you hit /64. If you're not concerned about aggregating networks, a common pattern on larger networks is to put the VLAN ID there in "false hex", i.e. VLAN 1357 = fd……:1357::/64. If you need more space you can either generate more random /48 prefixes, or widen the prefix length on your existing /48. The latter is technically against the spirit of ULAs, but… only the pedants will care.