Static IPv6 addresses for pots?

[keltia]

Is your feature request related to a problem? Please describe.
I'm trying to setup dual-stack pots (one per service) and while the IPv4 part with vnet is fine, I have issues with the IPv6 part.

Describe the feature you'd like to have
I want a way to specify a fixed IPv6 address (i.e. PREFIX::53 for a DNS jail or ::25 for a mail one), right now, I have to add the IPv6 address for the epairNb part manually in /etc/rc.conf inside the jail.

In pot.conf you can choose the IPv4 part but the is no way to put the IPv6 IP. Maybe I'm missing some SLAAC stuff but this is not described in the docs. I can setup rtadvd.conf to set the prefix but I want to have only fixed addresses.

Right now, everytime I get the pot running, I do not have an IPv6 address at all and no defaultrouter6 either.

Not working config:

epair3b: flags=8863<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=8<VLAN_MTU>
        ether 02:cd:af:16:d2:0b
        inet6 fe80::cd:afff:fe16:d20b%epair3b prefixlen 64 scopeid 0x4
        groups: epair
        media: Ethernet 10Gbase-T (10Gbase-T <full-duplex>)
        status: active
        nd6 options=23<PERFORMNUD,ACCEPT_RTADV,AUTO_LINKLOCAL>

When I add the IP and route, it works:

epair1b: flags=8863<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=8<VLAN_MTU>
        ether 02:e6:4b:df:7f:0b
        inet6 fe80::e6:4bff:fedf:7f0b%epair1b prefixlen 64 scopeid 0x4
        inet6 2001:470:1f15:563::53 prefixlen 64
        groups: epair
        media: Ethernet 10Gbase-T (10Gbase-T <full-duplex>)
        status: active
        nd6 options=23<PERFORMNUD,ACCEPT_RTADV,AUTO_LINKLOCAL>

and:

Internet6:
Destination                       Gateway                       Flags     Netif Expire
::/96                             ::1                           UGRS        lo0
default                           2001:470:1f15:563::1          UGS     epair1b
::1                               link#1                        UHS         lo0
::ffff:0.0.0.0/96                 ::1                           UGRS        lo0
2001:470:1f15:563::/64            link#4                        U       epair1b
2001:470:1f15:563::53             link#4                        UHS         lo0

Describe potential alternatives or workaround you've considered (if any)
I need to set every IPv6 manually.
(roberto@ here).

[pizzamig]

Hi. Thanks for reach out.
How do you configure the network when you create or clone your pot?
I guess you are using the public-bridge configuration.
In this case, IPv6 is directly attached to the network by adding the physical network interface of the host into the IPv6 bridge.
The jail, at start up, is going to execute rtsold to receive the network prefix from the network (the SLAAC part) and configure the IPv6 address using the mac address of the epair (as usual for rtsold).
Currently we don't support user-defined IPv6 addresses except for alias network configuration and we don't support mixed network configuration either (public-bridge for IPv4 and alias for IPv6).
Did I get your problem correctly?