[Samba] samba 4 migration with sambaSID duplicates

[Trenta sis]

Hi,

I'm testing to migrate samba 3 to samba 4 AD, and after execute check
duplciates appears that some  users and groups have sambaSID duplciates.
I have found that this users or groups, has correct entry user or group and
also an entry to ou=Idmap, and I'm not sure what I have to do...

this samba 3 was migrated from nt domain, and I'm not sure, but I think
that this was generated with nt domain...

I can't delete all entrys in ou=Idmap? what is this? What is the best
practices in this situation?

Thanks