disable ip-6 in bind9 and more

To avoid any timeouts or bumps in DNS resolving using Bind9 under Linux it is recommended to switch off support for ip6.

There are a few things to be done in a couple of steps:

Bind9 options

With Webmin:

Click on "Edit Config File"

Now select the file: /etc/bind/names.conf.options

Add the following:

dnssec-enable no;
filter-aaaa-on-v4 yes;

It should look like:

options {
    ...

    dnssec-validation no;

    dnssec-enable no;
    filter-aaaa-on-v4 yes;

    auth-nxdomain no;

    listen-on-v6 { any; };

    ...
};

Now save and close this file.

Modify bind9.service

It was recommended from another source that the step above would not be enough and that the bind9.service should also be modified:

 sudo nano /lib/systemd/system/bind9.service 

Change the following line by adding -f -4:

[Service]
...
ExecStart=/usr/sbin/named -f -4 $OPTIONS
...

Save the file and restart the Bind9 DNS server.

Last update: June 26th at 1:54pm