samba - Jan 2025 - Can a macOS (Posix) client see symlinks on FreeBSD server as symlinks on client?

Hello, Samba folks:

Is there a setting I could invoke, either on my server's Samba 
configuration or on my macOS smbfs configuration, which would make the 
hundreds of legacy symbolic links on the server's Posix file system 
appear as symbolic links on the macOS client?

Does Samba claim that it will present symlinks on the server file system 
as symlinks to a client?


Some background:

I have a macOS client which uses files from a small FreeBSD-based file 
server. I just switched from afp to smb as the way of connecting to my 
shares. With afp, my macOS client could create a Posix-style symbolic 
link on the server, and it would be stored as a Posix-style symbolic 
link on the server's file system. My macOS client saw symbolic links on 
the server's file system as symbolic links on the shared volume. These 
links are all internal to the directory trees of the share: think 
`../sibling/child/foo.txt` relative links.

Now, using smb, I don't have that behaviour. It appears that most of the 
symlinks on the server file system, which I created via an afp 
connection, now appear in my macOS clients as directories rather than 
symlinks.

Below is a local symlink, created on my client a year ago, then copied 
to the server via rsync over afp, and which is a symlink on the server's 
file system:

% ls -ld ~/Documents/Projects/2024/@@\ 2023 
/Volumes/MyShare/Projects/2024/@@\ 2023
lrwxr-xr-x 1 jdlh staff???? 7 Dec 30? 2023 
'/Users/myuser/Projects/2024/@@ 2023' -> ../2023
drwx------ 1 jdlh staff 16384 Dec 30? 2023 
'/Volumes/MyShare/Projects/2024/@@ 2023'

The macOS client view via smb of the FreeBSD symlink is some kind of 
simulated directory (see the "d" in the first column), while it sees
the
symlink on the local filesystem as a symlink (see the "l" in the first
column, and the arrow pointing to the link path).

Symbolic links which is create via the smb connection to this server do 
appear as symbolic links. On the server file system, they appear to be 
Minshall+French symlinks. They are 1067-byte text files with that format.

I have tried reading through the documentation to understand this, but 
I'm having a hard time finding documentation of these details for Samba, 
and the server configuration, and the client configuration.

The server is a TrueNAS version 13 NAS appliance, with FreeBSD OS and a 
ZFS filesystem. It appears to be running smbd Version 4.15.13. The 
global part of the smb4.conf file includes, "unix extensions =? yes".
I
don't see entries for the individual shares, but they must be 
somewhere.? I have checked a box in the admin UI which I think invokes 
"vfs_fruit", but I don't know how to be sure. "sudo
smbstatus" doesn't
seem to say.

The client runs a macOS Sonoma 14.7.2 OS, and Apples "smbfs" variant
of
Samba. `smbutil statshares -m /Volumes/MyShare` prints various 
attributes including, "SMB_VERSION SMB_3.1.1". My understanding is
that
this is plenty modern enough to support Posix well.

As I read the Samba website, especially the wiki, I don't find a page 
that says, "This is the behaviour which Samba provides with regards to 
symlinks."?? There are pages like 
<https://wiki.samba.org/index.php/SMB3-Linux>, which reads to me like an 
implementation design.? There are pages like 
<https://wiki.samba.org/index.php/UNIX_Extensions> which appear to be 
historical, but still show up in search results. Is there somewhere some 
documentation which tells me what the software actually does, rather 
than what it plans to do or used to do?

So: is there a way for me to get Samba server to present Posix symlinks 
to Posix clients as symlinks?

Thank you in advance for your help!
 ???? ?Jim DeLaHunt

-- 
.   --Jim DeLaHunt, jdlh at jdlh.com     http://blog.jdlh.com/
(http://jdlh.com/)
       multilingual websites consultant, Vancouver, B.C., Canada

On Sun, 5 Jan 2025 22:43:23 -0800
Jim DeLaHunt via samba <samba at lists.samba.org> wrote:
> Hello, Samba folks:
> 
> Is there a setting I could invoke, either on my server's Samba 
> configuration or on my macOS smbfs configuration, which would make
> the hundreds of legacy symbolic links on the server's Posix file
> system appear as symbolic links on the macOS client?
> 
> Does Samba claim that it will present symlinks on the server file
> system as symlinks to a client?
> 
> 
> Some background:
> 
> I have a macOS client which uses files from a small FreeBSD-based
> file server. I just switched from afp to smb as the way of connecting
> to my shares. With afp, my macOS client could create a Posix-style
> symbolic link on the server, and it would be stored as a Posix-style
> symbolic link on the server's file system. My macOS client saw
> symbolic links on the server's file system as symbolic links on the
> shared volume. These links are all internal to the directory trees of
> the share: think `../sibling/child/foo.txt` relative links.
> 
> Now, using smb, I don't have that behaviour. It appears that most of
> the symlinks on the server file system, which I created via an afp 
> connection, now appear in my macOS clients as directories rather than 
> symlinks.
> 
> Below is a local symlink, created on my client a year ago, then
> copied to the server via rsync over afp, and which is a symlink on
> the server's file system:
> 
> % ls -ld ~/Documents/Projects/2024/@@\ 2023 
> /Volumes/MyShare/Projects/2024/@@\ 2023
> lrwxr-xr-x 1 jdlh staff???? 7 Dec 30? 2023 
> '/Users/myuser/Projects/2024/@@ 2023' -> ../2023
> drwx------ 1 jdlh staff 16384 Dec 30? 2023 
> '/Volumes/MyShare/Projects/2024/@@ 2023'
> 
> The macOS client view via smb of the FreeBSD symlink is some kind of 
> simulated directory (see the "d" in the first column), while it
sees
> the symlink on the local filesystem as a symlink (see the "l" in
the
> first column, and the arrow pointing to the link path).
> 
> Symbolic links which is create via the smb connection to this server
> do appear as symbolic links. On the server file system, they appear
> to be Minshall+French symlinks. They are 1067-byte text files with
> that format.
> 
> I have tried reading through the documentation to understand this,
> but I'm having a hard time finding documentation of these details for
> Samba, and the server configuration, and the client configuration.
> 
> The server is a TrueNAS version 13 NAS appliance, with FreeBSD OS and
> a ZFS filesystem. It appears to be running smbd Version 4.15.13. The 
> global part of the smb4.conf file includes, "unix extensions =?
yes".
> I don't see entries for the individual shares, but they must be 
> somewhere.? I have checked a box in the admin UI which I think
> invokes "vfs_fruit", but I don't know how to be sure.
"sudo
> smbstatus" doesn't seem to say.
> 
> The client runs a macOS Sonoma 14.7.2 OS, and Apples "smbfs"
variant
> of Samba. `smbutil statshares -m /Volumes/MyShare` prints various 
> attributes including, "SMB_VERSION SMB_3.1.1". My understanding
is
> that this is plenty modern enough to support Posix well.
> 
> As I read the Samba website, especially the wiki, I don't find a page 
> that says, "This is the behaviour which Samba provides with regards
> to symlinks."?? There are pages like 
> <https://wiki.samba.org/index.php/SMB3-Linux>, which reads to me like
> an implementation design.? There are pages like 
> <https://wiki.samba.org/index.php/UNIX_Extensions> which appear to be
> historical, but still show up in search results. Is there somewhere
> some documentation which tells me what the software actually does,
> rather than what it plans to do or used to do?
> 
> So: is there a way for me to get Samba server to present Posix
> symlinks to Posix clients as symlinks?
> 
> Thank you in advance for your help!
>  ???? ?Jim DeLaHunt
> 
The problem with symlinks on Samba is that they require 'unix
extensions = yes', which requires SMBv1 (This parameter has been renamed
'smb1 unix extensions' in the latest versions of Samba) and by default
it is set to 'no'.

There is ongoing work for the SMBv3 version of 'unix extensions', but
at present (as far as I am aware) there is no support for symlinks and,
from the comments made by one of the Samba devs, it is unlikely to ever
support symlinks, though reparse points are likely.

Rowland