How does a server select a Domain Controller

What is the process for a server selecting the Active Directory domain controller? When a server requires a Domain Controller , what are the steps leading to a Domain Controller decision. I'm interested to understand - to troubleshoot some Clustering setup issues. 

These are the steps followed by a server communicating with Domain Controllers

STEP 1 :  Execute a Query against  the Primary DNS server , returning each Domain Controller (DC) in the domain 

                                            nslookup -type=srv _ldap._tcp.mydomain.net

STEP 2 : The server elects  the  first DC in DNS list using LDAP to connect

STEP 3 : Is the chosen DC in the same AD site site as the member server ? Based on information configured in AD sites 

        if yes --> server starts using the DC

        if no --->  DC will communicate to server member its site 

                                --> server will send new DNS query for the DC list for it's own site

                               --> Member selects the first DC in the DNS list , using LDAP to connect 

                                __>if no DC on local site - connect to any DC in the domain

Note:cache local site name in registry to speed up future request 

Useful commands using the nltest tool . The nltest tool is available if the AD DS or AD LDS server role is installed. 

--List trusted domains

nltest /trusted_domains

--List DCs in a specific domain 

nltest /dclist:mydomain

--Return the AD site of the current server

nltest /dsgetsite  

--List every DC registered the site name

nslookup -type=srv _ldap._tcp.mydomain.net

Read more 

 How to get the Active Directory Site subnets