dnsmasq and ipv6 config

[OzziGoblin]

Hi

I've been able to migrate to dnsmasq but there are some IPv6 settings I'm confused about.

I have been assigned a /48 IPv6 address by my ISP, it's segmented this into various /64s for each interface in OpnSense.  Each interface is configured with IPv6 Configuration Type of "Track Interface"  WAN as the parenjt address.
I used to use Router Advertisements, but I've been able to stop using that with the use of dnsmasq ranges, see below.



The question is, what setting do I need on each network interface for IPv6 Configuration Type, testing reveals I can disable it, but I'm not sure if that is correct.

Thanks for your help

[sifrmoja]

The official guide for IPv6 goes through setting up exactly what you are doing. What exactly are you struggling with?

[OzziGoblin]

Hi

Basically, if I'm using dnsmasq ipv6 RA modes to assign ipv6 addresses, do I need the setting enabled on the network interface to track the WAN and what should it be?

ATM each client is getting 2 ipv6 addresses, one seems to be from dnsmasq and the other appears be from the network interface

thanks

[sifrmoja]

Is the second one the privacy address? They both appear to be on the same /64.

Edit: it appears you are using DHCPv6 to send out client IPs as well as SLAAC. You should only use DHCPv6 for prefix delegation and maybe DNS server information.

[OzziGoblin]

Thanks, I think it's because I followed the instructions and used slaac,ra-names in dnsmasq.

[OzziGoblin]

In the end I've reverted to snapshot, I can't figure out the required IPv6 DHCP settings if not using ISC and RA.

Hopefully I can continue using ISC until I can get it working in a lab and then put into my system

[Monviech (Cedrik)]

Either you configure the IPv6 statically, or you use track interface and use the dnsmasq constructor, pointing each DHCPv6 range to the interface it should construct the RAs from.

E.g. this example works when having LAN on "Track Interface" /or/ a static IPv6 address

https://docs.opnsense.org/manual/dnsmasq.html#dhcpv6-and-router-advertisements

[muchacha_grande]

You can use the following guide as an additional source:

https://homenetworkguy.com/how-to/migrate-from-isc-dhcp-to-dnsmasq-or-kea-dhcp-in-opnsense/

I'm studying the migration right now as I'll be moving to dnsmasq in the following days.

[OzziGoblin]

Thanks, I did follow this guide

I'll be interested to hear how your migration goes, specifically around the interface IPv6 settings (tracking vs dhcp vs slaac) and the dnsmasq IPv6 dhcp ranges and their RA modes. Also whether you were able to completely remove ISC and dependancy on the seperate Router Advertisement service, as it's built into dnsmasq.
If you'd be willing to share how you went it would really be appreciated.  After spending too many hours researching, implementing and testing I wasn't able to get IPv6 working without duplicate addresses being assigned and Testipv6 failing so just reverted.

thanks