[Samba] Not your typical domain migration

[Scott Whitten]

Hi Guys,

I have three Samba file servers running different versions of CentOS and
Samba.  They are all joined to a proper Windows 2003 domain.

I'd like to migrate the WIndows domain to 2016 and all the Linux servers to
CentOS 7.

I can do Windows 2003->2012->2016 without too much trouble.

I'm concerned about the Samba side.  The servers are all using extended
file system permissions and extensive windows groups/permissions.  Would
the "idmap" range change?  Is there any way to mitigate this risk?

I realize I can follow the steps here:
https://wiki.samba.org/index.php/Setting_up_Samba_as_a_Domain_Member
to create the new servers and rsync the files/acls but how do I ensure the
permissions don't get lost and continue to work?  getfacl/setfacl?
Something else?

Any suggestions would be appreciated.