I have built a 4 node environment in which all 4 servers have CA and domain replication via a tight-cell topology.

I have some questions about redundancy and failover. 

1. How are user logins affected if my master dies? 

2. I understand that sssd has some built-in failover capabilities but is there anything that I need to do on the DNS SRV records for ldap and kerberos? 

3. Is failover even a thing for krb5/ldap services since they're replicating?

Overall,  I would like some detail about what to do and how, when my master goes down? I see a decent amount of information about how to set it all up but how do I actually make use of it in the event of server failure?

Any in-depth docs/info on this topic would be appreciated. 

Thanks in advance.