Symptoms

Attempt to create domain/subscription or add web hosting failed with error:

Unable to get SSL certificate by ID: 0

Cause

Database inconsistency

Resolution

Find a SSL certificate id from IP Addresses

mysql> select id,ip_address,ssl_certificate_id from psa.IP_Addresses\\G
*************************** 1. row ***************************
                id: 3
        ip_address: 123.123.123.123
ssl_certificate_id: 0
1 row in set (0.00 sec)

Get available certificates list

mysql> select id,cert_file, ca_file,name from psa.Certificates;
+----+-------------+---------+-------------------------+
| id | cert_file   | ca_file | name                    |
+----+-------------+---------+-------------------------+
|  1 | cerC535.tmp |         | Default Certificate     |
|  2 |             |         | Backup sign certificate |
+----+-------------+---------+-------------------------+
2 rows in set (0.00 sec)

Assign Default Certificate with id=1 to the IP address with id=3

mysql> update psa.IP_Addresses set ssl_certificate_id=1 where id=3;
Query OK, 1 row affected (0.05 sec)
Rows matched: 1  Changed: 1  Warnings: 0