[Dnsmasq-discuss] Cannot assign IPv6 address for /96 subnet

Simon Kelley simon at thekelleys.org.uk
Tue Feb 19 21:06:44 GMT 2013


So, I did some testing. I configured an server interface with 
prefix-length 96, and configured dnsmasq with a dhcp-range and 96 prefix.

Using dhclient, I got a lease successfully.

The only problem is that dhclient configured the client's interface with 
prefix-length 64.

I moment's thought shows that this is expected: there is nowhere in the 
DHCPv6 messages for the prefix-length information to be passed to the 
client. There _is_ a prefix-length field in router-advertisements. but 
AFAIK, there's no way for the DHCPv6 client to use that information.

Of course if you're using RA for address-allocation, using SLAAC, the 
prefix length has to be 64 anyway.

If anyone knows better, or can explain how the standard(s) are supposed 
to work, please enlighten me.

Simon.



More information about the Dnsmasq-discuss mailing list