there is a dhcp ipv6 server that can dynamically configurated?

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there is a dhcp ipv6 server that can dynamically configurated?

BABUT
the rad+slaacd scheme is described everywhere, but if Windows is used
instead of slaacd then when you change the prefix, Windows gets the
address from the new prefix, but does not remove the old one. as a
result ipv6 routing does not work. so i want to make a stateful
configuration in which(i hope) Windows will take new address and
remove old addresses. but i can not find the dhcp server in the config
where i can set a prefix as a "variable".
maybe there are other ways that are not obvious for me?

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Re: there is a dhcp ipv6 server that can dynamically configurated?

Stuart Henderson
On 2019-08-04, 3 <[hidden email]> wrote:
> the rad+slaacd scheme is described everywhere, but if Windows is used
> instead of slaacd then when you change the prefix, Windows gets the
> address from the new prefix, but does not remove the old one. as a
> result ipv6 routing does not work.

That is normal. The prefix is advertised with a "valid lifetime" and
"preferred lifetime". The default "preferred lifetime" is 604800 seconds
(7 days), "valid lifetime" is 2592000 seconds (30 days).

In IPv6 it is allowed / "normal" to have multiple addresses in different
prefixes at the same time. Seeing an advertisement for a new prefix does
not mean that an old prefix is invalid, it is treated as additional.

If you know that your prefix is going to change and the old one will become
invalid, these timers should be lowered, e.g. the following would set to
1 hour "preferred lifetime", 1 day valid lifetime.

interface vlan3 {
        auto prefix {
                preferred lifetime 3600
                valid lifetime 86400
        }
}

> so i want to make a stateful
> configuration in which(i hope) Windows will take new address and
> remove old addresses. but i can not find the dhcp server in the config
> where i can set a prefix as a "variable".
> maybe there are other ways that are not obvious for me?

I can't help with that, the only time I use DHCPv6 is for prefix
delegation (where I ask an upstream provider to tell me what
LAN prefixes to use), for everything else I just use slaac.