DHCPv6 with Windows 10

[wilj81]

This may be outdated, but I'm loosely following this to get DHCPv6 running in order to assign DNS for my pihole. However, after enabling Manual configuration and turning on DHCPv6 Windows 10 will no longer pull an IPv6 address. What's odd, is that it seemed somewhat borked in a fresh/default install of opnsense.

It's definitely broken with DHCPv6 enabled. Running ipconfig /renew6 returns this

Code Select Expand

An error occurred while renewing interface Ethernet : The cluster resource is not available.

Googling that I find nothing. Googling DHCPv6 setup on opnsense, I find a ton of folks having similar issues. I would greatly appreciate help in understanding what is going on here.

Thank you!

[bartjsmit]

This works for me:

- Fixed IPv6 address for the LAN interface inside the ISP assigned range
- RADVD running on the LAN interface with pi-hole IP configured as DNS

Check with radvdump in an OPNsense shell and let all LAN machines pick up a SLAAC address.

Bart...

[wilj81]

I'm guessing you needed to enable manual mode to get that to work?

[bartjsmit]

enable manual mode to get that to work?

Do you mean a manual IPv6 address on the LAN interface? It may also work with an address that tracks the WAN but my ISP delegates a static /56.

[wilj81]

I was referring to the setting shown in the attached image (bottom of the page on Interfaces -> [LAN])

[wilj81]

I set my pihole IP as DNS, but ipconfig /all never updates to that address.

[bartjsmit]

Step back a bit. There is no setting like that on the RADV page  ???

Go to Services, Router Advertisements, LAN

Router Advertisements: Unmanaged
Router Priority: High
Source Address: Automatic

Set the IPv6 address of your pi hole under DNS servers

Open a shell on the firewall and run 'radvdump'. Do you see advertisements every few minutes?

Restart the radvd service from the dashboard if needed.

Bart...

[wilj81]

You have to enable the checkbox in the screenshot I sent before "Router Advertisements" service is listed there.

In radvdump output I see advertisements every few seconds from by WAN interface. Is that what is expected?

Thank you kindly for your help!

[bartjsmit]

How do you get to that checkbox? I can't find it  :( Can you post the path from the root of the GUI please?

If I go Interfaces, LAN, there is no mention of radv. Maybe you need to undo the steps you took for DHCPv6?

IMHO there are actually very few cases where you need DHCPv6. A lot of people set it up because they are used to it in IPv4. Router advertisements take care of the basic networking (how do I get to my destination) and push out DNS settings. Most other services use multicast (IPv6 is big on multicast).

You need to see advertisements on your LAN interface. The ones on your WAN may be necessary for your ISP connection but it does nothing for SLAAC of your internal clients.

Bart...

[Greelan]

It appears if the IPv6 configuration type is Track interface

[wilj81]

For the checkbox go to Interfaces->[LAN] and then scroll to the very bottom. That's where I see that checkbox. I'm running 22.1.

I'm not currently using DHCPv6. The service is definitely not running.

If I go to Services->Router Advertisements->[LAN], there is where I'm setting the following:
Router Adv: Unmanaged
Router Priority: Normal
Source Address: Automatic
Advertise Routes:
     Prefix: [EMPTY], Length: 128

Do I need to put something in prefix or does it do that automatically (I'm assuming automatically)?

I've watched radvd output for sometime and never seen an advertisement other than WAN.

Lastly, the IPv6 Configuration Type under Interfaces->[LAN] is set to "Track Interface".

Again, your help is much appreciated - thank you!

[bartjsmit]

can you set the LAN interface to a static IPv6 inside your ISP range?

[wilj81]

Instead of "Track Interface"?

Meaning... set the IPv6 configuration type to "Static IPv6" and then assign an address?

[bartjsmit]

Yes, that only works if your ISP delegation itself is static though.

[wilj81]

ISP delegation is DHCP