Dan Purgert <d...@djph.net> writes: > Nicholas Geovanis wrote: >> On Thu, Apr 18, 2019 at 7:57 AM Michael Stone <mst...@debian.org> wrote: >> >>> >>> No, the ULA is the IPv6 equivalent of RFC1918 space--you can use it >>> internally without central registration by choosing a subnet from >>> fd00::/8. The space is so much larger that it's much less likely that >>> two sites would pick the same prefix, but there are no guarantees. >>> >> But isn't it irrelevant whether they pick the same prefix or not? Routers >> that respect ULA and RFC1918 shouldn't route any traffic destined to them >> off the logical subnet. Right? > > No. RFC1918 / ULA are merely "unroutable on The Internet" (as in, they > cannot be directly accessed from the public internet). You can freely > route between them on "private" networks to your heart's content. > > For example, I have the RFC1918 subnets > > - 192.168.1.0/24, .2.0/24, .10.0/24, and .20.0/24 (LAN networks) > - 10.90.0.0/16 (VPN[1]) > > [1] way overkill, but lets me move around a bit in case a hotel is using > part of that range. (I only have the server hand out a /24 out of that > range, but the LAN's routing table uses the full /16).
I use 192.168.13/24 for my home machines, externally available on my VPN as 10.13.13/24, on the theory that hotels will be sensitive to offending superstitious guests. Haven't had a problem yet!