AD Bind fails 25.10.1 [EFAULT] The DNS query name does not exist: 103.1.168.192.in-addr.arpa

TrueNAS General
1

Recently my AD bind on my primary TrueNAS box broke I forgot to capture the error before unbinding to rebind. When trying to rebind after clearing the existing kerberos realm and keytabs I get this error “[EFAULT] The DNS query name does not exist: 103.1.168.192.in-addr.arpa.”

I am not sure what that DNS query is even attempting to do. I can nslookup my domain and each DC and they all return normally. Nothing has changed on the AD side, I did upgrade to 25.10.1 a few weeks ago though and the issues did not start until then. It has been happily running for months.

Recently I built a second box for off site backup on a Dell Poweredge R530 and it behaves exactly the same way, both when it was on site and in its remote location over the site to site link.

I have confirmed that other devices can join AD normally. Fresh Windows VMs and my Macbook happily join using the same credentials I am using with TrueNAS

AD setup: Three Server 2025 VMs running on Proxmox all updated and freshly rebooted. DCs are the DNS servers handed out in DHCP in my Unifi UDM Pro.

Primary TrueNAS box:

Scale 25.10.1

Threadripper 1950X

ASrock Fatal1ty X399 Professional Gaming Motherboard

128GB of non-ecc memory

Broadcom/LSI SAS3008 HBA

Dual ConnectX4

Nine HUS728T8TALN6L0 8TB hard drives

Seven Western Digital SN730E NVMe drives

2

Do you have a reverse zone defined here? This error indicates that we failed a reverse lookup of a KDC, which is very surprising. Is this non-microsoft DNS?

3

OMG I have been staring and searching for errors like that for so long I did not even notice that was the DC’s IP backwards……

I did not have a reverse lookup zone, so I just created one for that subnet. All the DNS in the network is pointed at the domain controllers so everything is Microsoft.

That fixed it! Thank you sooooo much, I have been fighting with this for hours.