[Samba] issues after migration

[Trenta sis]

hi,

recently we have migrated from samba 3 nt domain to samba 4 ad, 4.4.5

After this migration we have detected two issues:
1. some machines appear that can't contact with domain, checked ip, dns...
all correct but can't login domain not available... as workaround ifwe
rejoin machine then can reauthenticate to domain..
2. some machines win2003 and win2008 a windows firewall is enabled after
migration, then we disable manually and begins to work. we have checked if
it is a gpo, but after migration we don't use any gpo or specian change on
this config


thanks