Question 1 : Publisher role in the cluster (besides central configuration and administration). Does it keep a database of all endpoints? Does Insight provide complete view of all nodes?...etc.
Answer 1 : Endpoint Database and authentication information is replicated along with general system configuration however accounting data is not replicated. Re Insight replication, this depends on where you have enabled Insight.
Question 2 : What is the effect of losing the Publisher (say we do not have a backup), beside configuration sync. Does any CPPM service stop, or gets hindered?
Answer 2 : If you lose a Published there re two immediate downsides….you are unable to create new guest accounts and OnBoard new devices and the reason is because the Publisher is the only node that WRITES to the SQL Database. So to enable this function in a cluster where the Publisher has failed requires that you promote a Subscriber to be a Publisher.