Tak ja si taky odpovim sam. Pote, co se za mesic nic nezmenilo, zastrelil jsem dhclient -6, smazal jsem nasledujici soubory:

• /var/lib/dhcp/dhclient6.eth0.leases

• /var/lib/dhcp/dhclient6.leases

• /var/lib/dhcpv6/dhcp6c_duid

a pustil znova dhclient -6 -P -N -v eth0

A ejhle:

Listening on Socket/eth0
Sending on   Socket/eth0
Created duid "\000\001\000\0012.\002b\000\021\011....
PRC: Soliciting for leases (INIT).
XMT: Forming Solicit, 0 ms elapsed.
XMT:  X-- IA_NA 09:cc:f7:c8
XMT:  | X-- Request renew in  +3600
XMT:  | X-- Request rebind in +5400
XMT:  X-- IA_PD 09:cc:f7:c8
XMT:  | X-- Request renew in  +3600
XMT:  | X-- Request rebind in +5400
XMT: Solicit on eth0, interval 1050ms.
RCV: Advertise message on eth0 from fe80::201:....
RCV:  X-- IA_NA 09:cc:f7:c8
RCV:  | X-- starts 1788560867
RCV:  | X-- t1 - renew  +1296000
RCV:  | X-- t2 - rebind +2073600
RCV:  | X-- [Options]
RCV:  | | X-- IAADDR 2a02:8302:....
RCV:  | | | X-- Preferred lifetime 2592000.
RCV:  | | | X-- Max lifetime 3456000.
RCV:  X-- IA_PD 09:cc:f7:c8
RCV:  | X-- starts 1788560867
RCV:  | X-- t1 - renew  +1296000
RCV:  | X-- t2 - rebind +2073600
RCV:  | X-- [Options]
RCV:  | | X-- IAPREFIX 2a02:8308:....::/56
RCV:  | | | X-- Preferred lifetime 2592000.
RCV:  | | | X-- Max lifetime 3456000.
RCV:  X-- Server ID: 00:01:00:01:5b:31:f2:80:00:....
RCV:  Advertisement recorded.
PRC: Selecting best advertised lease.
PRC: Considering best lease.
PRC:  X-- Initial candidate 00:01:00:01:5b:31:f2:80:00:.... (s: 20204, p: 0).
XMT: Forming Request, 0 ms elapsed.
XMT:  X-- IA_NA 09:cc:f7:c8
XMT:  | X-- Requested renew  +3600
XMT:  | X-- Requested rebind +5400
XMT:  | | X-- IAADDR 2a02:8302:0:....
XMT:  | | | X-- Preferred lifetime +7200
XMT:  | | | X-- Max lifetime +7500
XMT:  V IA_NA appended.
XMT:  X-- IA_PD 09:cc:f7:c8
XMT:  | X-- Requested renew  +3600
XMT:  | X-- Requested rebind +5400
XMT:  | | X-- IAPREFIX 2a02:8308:.../56
XMT:  | | | X-- Preferred lifetime +7200
XMT:  | | | X-- Max lifetime +7500
XMT:  V IA_PD appended.
XMT: Request on eth0, interval 920ms.
RCV: Reply message on eth0 from fe80::201:....
RCV:  X-- IA_NA 09:cc:f7:c8
RCV:  | X-- starts 1788560868
RCV:  | X-- t1 - renew  +1296000
RCV:  | X-- t2 - rebind +2073600
RCV:  | X-- [Options]
RCV:  | | X-- IAADDR 2a02:8302:....
RCV:  | | | X-- Preferred lifetime 2592000.
RCV:  | | | X-- Max lifetime 3456000.
RCV:  X-- IA_PD 09:cc:f7:c8
RCV:  | X-- starts 1788560868
RCV:  | X-- t1 - renew  +1296000
RCV:  | X-- t2 - rebind +2073600
RCV:  | X-- [Options]
RCV:  | | X-- IAPREFIX 2a02:8308:..../56
RCV:  | | | X-- Preferred lifetime 2592000.
RCV:  | | | X-- Max lifetime 3456000.
RCV:  X-- Server ID: 00:01:00:01:5b:31:f2:80:00:21:5e:ed:2c:61
PRC: Bound to lease 00:01:00:01:5b:31:f2:80:00:21:5e:ed:2c:61.

Mnohem lepsi. Zjevne si skutecne nekde pamatoval ze jsem puvodne ten prefix nechtel a ignoroval ze jsem zmenil nazor.

(Krome noveho prefixu se take zmenila ta normalni adresa a default-duid, at je to co je to.)

Dualstack je/začíná být dostupný pouze v bridge režimu nebo i ve výchozím router režimu?

Já mám modem v režimu router a dualstack mě jede.