OPNSense no longer supports multiple DNS servers??

[hakuna]

Hi all,

This is my setup:

i5 16GB baremetal running Proxmox:

• OPNsense 23.7.1_3
• DNS01: Pi-Hole + Unbound Recursive DNS
• DNS02: Pi-Hole + Unbound Recursive DNS
• WireGuard VPN

Add both DNS under:

• System > Settings > General
• Services > DHCPv4 > LAN

I have had this setup for years and it always worked flawlessly for years.
I am upgrading the baremetal with an i7, 32GB, NVMe to allow OPNSense to have more resource since I am exploring more network plugins and firewall and 1G plan which is currently punishing its limited resources.

Well, I started by setting up the new DNS02, then kill the old DNSs to make sure everything was working, well, the internet stopped working!!
Back in the day I could always bring DNS01 down and OPNSense would always redirect the DNS requests to the DNS02 like nothing happened, it was beautiful and the reason why I have both DNS VMs.

Well, I thought it was the problem with the new VM so shut all the new setup down, and check the environment that has been running for years.
Shut DNS01 and the whole internet stops. DNS02 is no longer receiving the DNS requests as it used to so this is not a new setup problem.

I even tried to manually remove DNS01 from OPNSense which didn't work either but this is so wrong. I never used to have to do that.

My question is: Why is OPNSense no longer balancing the DNS requests between DNS01 and DNS02 as it used to??
If I shut DNS01 right now, the whole internet goes RIP like if the DNS02 did not existed.

I have firewall rules in place to only allow Pi-Holes to resolve DNS requests, redirect any DNS request to them and IoT with hard coded DNS from bypassing it with Outbound rule.
This setup has been working flawlessly for years so I have no idea what changed on the OPNSense level.

And before I starting going crazy, I would like to know what changed and how to fix it.
I do not remember when was the last time I left only DNS02 running to fully refresh Pi-Hole/Unbound caching, I know it was a few months back but I cannot remember when so perhaps that could indicate version/bug??

Thank you

[CJ]

What do you get in Interfaces: Diagnostics: DNS Lookup when one of your DNS servers is down?

Additionally, are the clients working or are they having trouble as well?