After upgrading server to MariaDB, SuiteCRM can no longer connect to database

I’m running SuiteCRM on a DigitalOcean Centos 7 droplet. After switching from MySQL to MariaDB, the site no longer opens. The error message in the error log is

Uncaught Exception: Could not connect to the database. Please refer to suitecrm.log for details. in /home/domain/public_html/crm/include/utils.php:1687
Stack trace:
#0 /home/domain/public_html/crm/include/database/MysqliManager.php(290): sugar_die('Could not conne...')
#1 /home/domain/public_html/crm/include/database/DBManagerFactory.php(147): MysqliManager->connect(Array, true)
#2 /home/domain/public_html/crm/include/entryPoint.php(179): DBManagerFactory::getInstance()
#3 /home/domain/public_html/crm/cron.php(45): require_once('/home/domain/p...')
#4 {main}
  thrown in /home/domain/public_html/crm/include/utils.php on line 1687

The suitecrm log ellaborates:

[FATAL] Could not connect to DB server as banksia_crm. port : Host '2400:6180:0:d0::44a1:9001' is not allowed to connect to this MariaDB server
Tue Jul  4 00:10:39 2017 [20525][-none-][FATAL] Could not connect to DB server as domain_crm. port : Host 

I completely deleted and then successfully reinstalled suitecrm.

Try connecting to your suiteCRM database using a query browser tool. if you unable to connect via that tool then probably you have to fix the db connection and then everything will works fine
tool :