[Dnsmasq-discuss] DHCPv6 and prefix length on clients

[Roy Marples]

On 2014-07-19 15:53, Niels Penneman wrote:
> ... but it has a prefix length of 128. Hence, the VMs cannot see each 
> other.
> 
> My configuration explicitly specifies a prefix length of 64; what could
> cause the prefix length to be set to 128 on the DHCPv6 client side?

DHCPv6 addresses have no prefix length, they are just an address, so 
always a /128.
What you need to do is advertise a /64 prefix, but with the M bit set 
and the AUTOCONF bit disabled.

That way the hosts you want off the IPv6 network will be aware of the 
prefix, but won't have a global address on it.

Roy