MariaDB and mysql

[#1]

We are installing HDP 2.6.1 with RHEL7.4. The existing backend database we used for Ambari, Ranger, Oozie, & Hive is mysql version 5.1.73-3.el6_5. RHEL7.4 comes with mariadb. Should we install the same version of mysql since we will continue to use the mysql databases? RHEL7 now comes with mariadb .5.56-2..

Thanks,

[#2]

Please note that HDP 2.6.1 is supported on RHEL 7.0, 7.1, 7.2.

7.4 is not supported,

https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.6.1/bk_support-matrices/content/ch01.html