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

Symptoms

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

  CONFIG_TEXT: DNSPROBE FINISHED ERROR

• Domain cannot be resolved locally with explicitly specified NS:

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

• Ubuntu dist-upgrade may have been performed recently

• BIND service status shows configuration 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

• The command above may show BIND service in "activating" state and service restart does not help.

Cause

BIND configuration is not correct.

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