On Fri, Jul 8, 2022, 09:22 Andrei Borzenkov <[email protected]> wrote:
> On 07.07.2022 18:25, Bent Bagger wrote: > > > > The prefix delegation problem starts with the interactions between net0 > > and net2. Net0 is delegated a /56 prefix from the main router (which > > runs radvd and dhcpd6, not networkd, for historical reasons). I want > > net2 to delegate a /60 subnet to net3, but it doesn't happen. > > > networkd does not support prefix subdelegation. It supports querying > upstream for delegated prefixes and allocating one /64 received prefix > to downstream interface announcing it via RA. The same functionality as > NetworkManager. Nor does networkd support DHCPv6 server functionality. > > For all practical purposes IPv6 on-link prefix can only be /64. So > "delegated a /56 prefix" is misleading. You get delegated block of > prefixes that are aggregated into /56 mask. > IME, "prefix" is a *very* common term for routed prefixes, not only on-link ones – probably much more common than "/56 mask" (given that nothing uses actual mask notation in IPv6). The upstream router doesn't care about whether you're going to use it as on-link prefixes or not, anyway.
