Domains hosted on Plesk server cannot be accessed: DNSPROBE FINISHED ERROR

Symptoms

• Domains hosted on Plesk server cannot be accessed with an error in browser like:

  CONFIG_TEXT: DNSPROBE FINISHED ERROR

• Domain cannot be accessed locally with explicitly specified NS:

  # dig +short exampe.com @ns1.example.com
  #

• Dist-upgrade to Ubuntu 20 may be performed recently

Cause

BIND misconfiguration. there are missing options like below:

# systemctl status bind9
* named.service - BIND Domain Name Server
Loaded: loaded (/lib/systemd/system/named.service; enabled; vendor preset: enabled)
Drop-In: /lib/systemd/system/bind9.service.d
`-respawn.conf
Active: active (running) since Sat 2020-10-03 02:18:00 GMT; 20min ago
. . .
`-236526 /usr/sbin/named -f -u bind

Resolution

1. Connect to the server via SSH

2. Edit /etc/default/named config file, replacing OPTIONS parameter.

   Before:

   # cat /etc/default/named
   . . .
   OPTIONS="-u bind"

   After:

   # cat /etc/default/named
   . . . 
   OPTIONS=" -t /var/named/run-root -c /etc/named.conf -u bind -n 2"

3. Restart BIND service:

   # systemctl restart bind9​

4. Repair DNS for domains:

   # plesk repair dns