After a bit of research, the fix in my case was to “GRANT” user root to connect to MySQL on any hosts. By default, user “root” was only allowed to connect to localhost and 127.0.0.1 hosts of MySQL.
#GRANT ALL PRIVILEGES ON *.* TO ‘root’@’%’ IDENTIFIED BY ‘<roots-password>’ WITH GRANT OPTION;
via ERROR 1130 (HY000): Host ‘hostname’ is not allowed to connect to this MySQL server – kuber’s posterous.