OPNsense Forum

English Forums => General Discussion => Topic started by: securid on February 20, 2022, 12:35:27 pm

Title: troubleshooting dhcpv6
Post by: securid on February 20, 2022, 12:35:27 pm

Hello everyone,

I read https://forum.opnsense.org/index.php?topic=7149.0 and the links it refers to. My situation is a little different. Ive setup dhcpv6 on pfsense before but then it pfsense was the router and firewall as well.

My router is a Unifi UDM pro. I don't like how it does dhcp/dns so I disabled that. Its WAN interface has a provider ipv6 address in a /56. Lets say its ipv6 address is 2001:abcd:1234:0:0443:7e37:7caa:4acb.

I have opnsense running in a vm with a single interface, firewall is disabled and I am only using LAN with DHCP, DHCPv6, Unbound and NTP server.

I configured the LAN interface with a fixed ipv6 in a /64 within the /56 of the WAN interface.
Let's say its 2001:abcd:1234:1:192:168:1:1 :D

I configured DHCPv6, enabled it and it picks up the subnet /64 and shows the correct available range. I configured the range as:
2001:abcd:1234:1:192:168:1:ff - 2001:abcd:1234:1:192:168:1:ffff

Prefix delegation range is empty, delegation size is 64.
I entered a DNS server, NTP server with ipv6 addresses. The rest is default.

For router advertisement I chose:
RA: Assisted
Prio: High
Source address: auto
advertise: enabled
DNS servers: 1 address
The rest is default.

The problem is, my clients get an ipv6 address, but its outside the range of what I configured. Opnsense never shows a lease and the logs are empty. I suspect its getting an address from my ISP via the router WAN interface, but I don't have logging to confirm that.

On the UDM, there is no DHCP running, no ra daemon.

Im not sure whats happening, I can ping the router and opnsense on v6  but how do I get it to use opnsense dhcpv6?

Thanks for the help!

Title: Re: troubleshooting dhcpv6
Post by: npiersma on December 02, 2022, 09:35:47 pm

Late response, but did you get this working? I've the same lame issue, where I can see my client is getting a ipv6 address but outside the subnet of the interface providing dhcpv6.
Cheers
NIels

Title: Re: troubleshooting dhcpv6
Post by: securid on December 03, 2022, 07:18:29 pm

No, I didn't like the UDM at all so I sent it back a couple of days after purchase.

Title: Re: troubleshooting dhcpv6
Post by: ylu on December 04, 2022, 07:53:39 am

Maybe we have the same problem.the dhcpv6 service didn't start normally.https://forum.opnsense.org/index.php?topic=31324.0

Title: Re: troubleshooting dhcpv6
Post by: nbari on April 07, 2023, 02:29:28 pm

I am having the same problem with the latest OPNsense 23.1.5_4-amd64, the same configuration used to work in PFSense, any ideas on how to fix this?