@lekhu i will try explain from what i understand of ucs “works”
note: i’m difficult to setup it for me…
For your case, i assume you have samba4 installed (ucs working as ad directory) so i assume you have the package active directory connection installed in both servers:
As windows don’t have a master/slave concept both of your servers works as netlogon, so when a user do the login process what happens is a bit of “microsoft magic” as in… the user can do the login in your pdc or in your member server, so the userfolders are created, however because don’t exist none synchronism method between the servers… the files aren’t replicated…
View this topic, maybe you can understand it better How-to: Samba Homes and Shares - Basics