Need Info on SSL Certificates on FileMaker Server 17

[fmbug]

Hi All,

 

Scenario: 

We have 7 Severs -  3 DB ( xyz1.abc.com (Database Server), xyz2.abc.com (Database Server) & xyz3.abc.com (Web Server (Child of xyz2.abc.com) ) and 3 Citrix Servers where FileMaker client is installed (xyz4.abc.com, xyz4.abc.com & xyz4.abc.com ). 

 

Current relationships are as below:

 

xyz1>>xyz4, xyz5, xyz6

xyz2>>xyz4, xyz5, xyz6

xyz3>>xyz4, xyz5, xyz6

xyz1<<>>xyz2

xyz2>>xyz3

 

Could you please help us to know how many SSL Certs we need to purchase in case SAN type?

 

If we need to purchase SSL certificates from other vendors which are not listed in FileMaker CA, can we purchase it from them and one more concern will that be working fine in FM Server?