ISPConfig Debian 12.12 Bind9 IPv6 (Does not resolving)

Hi,.

Our ISPConfig server, which runs behind Proxmox, is unable to resolve IPv6 addresses via BIND9. When we disable BIND9, the installation completes successfully. However, Let’s Encrypt never works—whether “Skip Let’s Encrypt Check” is enabled or disabled.

Below, you will find the configurations of both Proxmox and ISPConfig, as well as the errors that occur when “Skip Let’s Encrypt Check” is selected and when it is not.

We've been trying to solve this issue for 12 hours without success. Could you please help us?

Proxmox Server (Linux 6.17.2-1-pve) ip configuration

Proxmox Server (Linux 6.17.2-1-pve) cat /etc/resolv.conf

Proxmox Server (Linux 6.17.2-1-pve) cat /etc/hosts

Proxmox Server (Linux 6.17.2-1-pve) cat /etc/hostname

Proxmox Server (Linux 6.17.2-1-pve) ip a

Proxmox Server (Linux 6.17.2-1-pve) iptables -L -n -v

Proxmox Server (Linux 6.17.2-1-pve) cat /etc/iptables/rules.v4

Proxmox Server (Linux 6.17.2-1-pve) IPv6 Rules cat /etc/iptables/rules.v6

Virtual Machine (Debian over ISPConfig)

Debian 12.12 ISPConfig cat /etc/hostname

Debian 12.12 ISPConfig cat /etc/hosts

Debian 12.12 ISPConfig cat /etc/resolv.conf

Debian 12.12 ISPConfig cat /etc/hosts

Debian 12.12 ISPConfig ip a

Skip Lets Encrypt Check (Enabled Log)

Skip Lets Encrypt Check (Disable Log) Not Checking...

 

You are better of to get support from Proxmox forum regarding its IPV6 setup. In general it is only available if your PVE is setup for the same and then allow your ISPConfig VM to use the same as well.

 

For those facing the same issue:

The problem occurs because Linux, by default, tries to make IPv6 DNS requests. As a result, BIND9—running behind NAT—attempts IPv6 queries instead of IPv4 queries, and therefore fails.

If you are getting an error during the PhpMyAdmin installation step, you have two solutions:
A. Enable IPv6 traffic
You can do this via iptables routing.
B. Disable IPv6 in BIND9
This is usually the easier method.

Summary
Before starting the ISPConfig installation, install BIND:

Code:

apt install bind9 bind9utils bind9-dnsutils dnsutils

Then edit:

Code:

nano /etc/default/named

Configure BIND9 to use only IPv4.
It should look like this:

Code:

OPTIONS="-4 -u bind"

Finally, add the following to your /etc/resolv.conf:

Code:

nameserver 127.0.0.1

With this setup, you will not encounter any errors.

 

IPConfig must be installed on clean machine, virtual or not, and also bind is installed by default, unless you opt not to install it.

 

And besides that is bind not the system's default resolver after a normal installation (a clean base system and ispconfig on top of that).

You have created noting more than a workaround and have not solved the real issue your system is having!

 

Hi @remkoh
I guess you’re having a bit of a rough day.
In my case, the virtual machine is behind Proxmox and shares the same IP as Proxmox. Also, I don’t have a public IP available for the virtual machine. So I only had two options:

• Set up NAT forwarding with iptables
• Disable IPv6

We could have installed ISPConfig with the -no-dns flag and used Bind, but configuring it properly would have been much more complicated given the current setup.

Of course, if you have a better solution, I’d be happy to try it.

 

1. It is fine to share a public IP between proxmox.and its vm(s). One public IP, even it is only an ipv4, can be used by many applications at a time, if you know how to.manage it properly.

2. Your problem to me is you have setup your proxmox with ipv6 as well as your vm, the easiest way out is actually to set them without it, though I dont think you even need bind9 for it if you cannot / do not run dns server.

3. But then, managing ipv6 is also not so difficult to few, and could give an admin various advantages, though turning it off works well for many who are still learning it and having a very hard time to make it work. May be work it in your own free time in some test vm's will do best.

But those are just my thoughts spoken out loud.

 

Thank you for sharing your thoughts.
If you don’t mind, could you kindly outline the basic principles or best practices for assigning a public IP from Proxmox to a virtual machine? We try to understand what is wrong..
I can also share proxmox and vm's password details if you have time to reply original question.

 

Just stating facts. My day was fine by the way.

I'm running multiple debian and ubuntu servers on multiple proxmox nodes (actually pimox on armbian) both as vm and lxc behind my single ip home internet connection myself.
Though not running ispconfig, which is totally unrelevant, non of them have bind installed and set as resolver to get resolving going.
All resolve just fine after installation and configuration. And after proper installation and configuration of proxmox!
I'll give you a hint: look into "ifupdown2"

 

https://www.google.com/search?q=single+public+ip+for+proxmox+and+all+vms

Google Search (now with Ai) can already help you to achieve what I said earlier, basically either routing or proxy settings shiuld do it.