[Samba] Setting up ACL definitions in smb.conf for maximum Windows server compatibility

[Rowland Penny]

On 14/01/2023 17:22, Peter Milesson via samba wrote:

> Hi Rowland,
> 
> Thanks for the input.
> 
> The DC with Louis' packages will be next in line for replacement. I have 
> noticed there have not been any updates for quite a while.
> 
> I wasn't aware that the rid backend makes all AD users Linux users. It 
> is definitely not clear from the Wiki. Will it pose a problem with 
> compatibility on Windows workstations when accessing the shares?

It would be a bigger problem if your users (and groups) didn't have 
Linux ID's

The 'rid' idmap backend calculates the Linux ID from the AD objects RID, 
so if you use the same basic smb.conf on all Samba machines, the user or 
group will always get the same Linux ID. To get this all to work, you 
need to set up nsswitch.

One other thing you need to be aware of, unlike earlier versions of 
Samba, you do not create local Unix users, you just create users and 
groups in AD and Samba will map them to Unix ones.

> Will 
> there be any limitations, or otherwise crippled behavior? Anyway, there 
> will be no access allowed to the server outside Samba, except for Linux 
> administration tasks. Is there a simple way to migrate to ad backend 
> from rid? 

You would still have the same non problem, for your users to store data 
on the Unix domain member, they need to be known to the Linux machine, 
so you would have to give every user a uidNumber attribute and Domain 
Users would have to have a gidNumber attribute.

> Otherwise I see a daunting task before me setting new 
> permissions on everything according to each user's permission mix.

Which is why you set them via Windows and use groups.

> 
> So the two lines
> 
>     vfs objects = acl_xattr
>     map acl inherit = yes
> 
> are actually sufficient for getting the best Windows server 
> compatibility, without the other options?

Yes, one of the lines is actually set for you because of the vfs_objects 
line and you do not need the others if you set the permissions from Windows.

> 
> I have never used anything else than the RSAT tools (AD, DNS, GPO) to 
> manage the share permissions on the existing server. I have no intention 
> to use anything else on the new server, unless absolutely required.
> 
> About setting up the profile share, I would very much try to avoid using 
> roaming user profiles. I have been using folder redirection for quite 
> some years, and it is definitely much more efficient than roaming 
> profiles. There are quite a few users that insist in cluttering their 
> desktops with 10's of GB of files, even if I tell them 500 times, that 
> they shouldn't be surprised that it takes several minutes before they 
> are logged in. With folder redirection that problem is gone.

We have a page for that as well:

https://wiki.samba.org/index.php/Configuring_Windows_Profile_Folder_Redirections

Rowland