Unable to create a domain alias in Plesk: DNS record already exists

Symptoms

When creating a new domain alias, the operation fails with the following error message in Plesk (in this example, domain alias example.net for example.com):

PLESK_ERROR: Error: Unable to add the ipv4.example.net. IN A 203.0.113.2 record to zone example.net: DNS record already exists.

Cause

The domain, for which a domain alias is created, contains duplicate DNS records.

In this example, there is a duplicate DNS entry for example.com that points to the same IP address 203.0.113.2 at Domains > example.com > DNS Settings.

Resolution

1. Log in to Plesk.

2. Go to Domains > example.com > DNS Settings.

3. Select the duplicate DNS entries and remove them.

   Note: If the domain's DNS zone is hosted externally (only NS records are shown), see the solution below.

   
   
   
   

4. On the next page, click Update to apply the changes.

If the domain's DNS zone is hosted externally (only NS records are shown):

1. Connect to your Plesk server via SSH.

2. For safety reasons, create a backup of the Plesk system database:

   # plesk db psa > /root/psa_dump.sql

3. Access Plesk database:

   # plesk db

4. List duplicated entry mentioned in the error message for domain example.com (for which alias domain should be created):

   MYSQL_LIN: MariaDB [psa]> select * from dns_recs where host='example.com.' and type='A'\G
   *************************** 1. row ***************************
   time_stamp: 2025-03-14 17:58:57
   id: 83
   dns_zone_id: 2
   type: A
   host: ipv4.example.com.
   displayHost: ipv4.example.com.
   val: 203.0.113.2
   displayVal: 203.0.113.2
   opt:
   external_id:
   ttl: NULL
   *************************** 2. row ***************************
   time_stamp: 2025-03-14 17:58:57
   id: 96
   dns_zone_id: 2
   type: A
   host: ipv4.example.com.
   displayHost: ipv4.example.com.
   val: 203.0.113.2
   displayVal: 203.0.113.2
   opt:
   external_id:
   ttl: NULL

5. Delete the extra record using its ID:

   MYSQL_LIN: MariaDB [psa]> DELETE FROM dns_recs WHERE id = 96;