Leopard and samba shares

diamondT · 10-28-2007, 10:13 PM

Hi,

I have a couple of samba shares on a linux machine and I try to access them from Leopard/Finder. In these shares there exist some symbolic links. In Tiger everything worked just fine. But in Leopard, Finder tries to translate these links to the local filesystem, which of course results to the links being dead.
Since I did not change my samba server settings and since everything was OK in Tiger I suspect this is a Leopard-specific prob.
Any ideas?

Tnx in advance.

CAlvarez · 10-28-2007, 10:25 PM

Sorry, no ideas, except to say that I also have had a few issues with Linux Samba shares and Leopard for some time, no solutions.

sonicbuddha · 10-30-2007, 12:23 AM

I have this problem, too. I've tried troubleshooting by adding

follow symlinks = yes

to my smb.conf file (it should be active by default) with no results. Other than the symlinks that point outside the exported smb tree being broken, it the functionality seems normal. Although, honestly, this is an upgrade deal breaker for me.

diamondT · 10-30-2007, 09:38 AM

Quote:

Originally Posted by sonicbuddha


	I have this problem, too. I've tried troubleshooting by adding follow symlinks = yes to my smb.conf file (it should be active by default) with no results. Other than the symlinks that point outside the exported smb tree being broken, it the functionality seems normal. Although, honestly, this is an upgrade deal breaker for me.

Yeap, I forgot to mention that the broken links point outside the exported tree.

There is another option for the samba server: "wide links = yes" but is it *also* enabled by default so it shouldn't make any difference...

MontyPython42 · 10-30-2007, 03:28 PM

Leopard's SMB/CIFS supports the Unix Extensions, which include support for server-side symbolic links.

I haven't yet figured out how to leave the Unix Extensions enabled while only disabling the symlinks (or making the SMB server handle them), but if you add

Code:

unix extensions = no

to the server's smb.conf, that should fix the issue.

diamondT · 10-30-2007, 05:07 PM

Nope it doesn't

I added "unix extensions = no" to smb.conf of the server, restarted the samba daemon, even restarted Leopard but the problem still exists...

For the record, accessing the share from a windows machine works as expected. It seems more and more like a Leopard specific prob.

sonicbuddha · 10-31-2007, 06:01 PM

Ok, so I've done some troubleshooting. If I access the share utilizing smbclient, the links work as they are supposed to and resolve. If I attempt to mount the share using mount_smbfs and all I get is :

# mount -t smbfs //<user>:@<server>/<share> <path to test mount point>

mount_smbfs: failed to initialize the smb library: invalid argument

Which might just be my usage. BUT, if I mount the share via the Finder and access the share via the command line through terminal, the links work as they are supposed to and resolve. Yet if I try to open a directory with the "open" command, the Finder fails. Trying to open files, on the other hand, succeed.

Bottom line, this is a Finder issue.

BartVB · 10-31-2007, 06:26 PM

Same problems here. Haven't tried resolving this yet but I did notice that those symlinks did work yesterday. No idea what was different then. I certainly didn't change anything on the Samba side (Debian Lenny machine) and normally I connect with cmd-k and the URL smb://192.168.1.1/storage

As I said, no idea why this worked yesterday but doesn't work today. It sure is an indication that this is some kind of fluke on the Leopard side.

sonicbuddha · 11-11-2007, 05:37 PM

Quote:

Originally Posted by MontyPython42


	Leopard's SMB/CIFS supports the Unix Extensions, which include support for server-side symbolic links. I haven't yet figured out how to leave the Unix Extensions enabled while only disabling the symlinks (or making the SMB server handle them), but if you add Code: unix extensions = no to the server's smb.conf, that should fix the issue.

I can confirm this works. It sucks, but it works. When unix extensions are disabled, the entire share is owned by the user who mounts it, which is completely insecure. I can also confirm that this is samba, not Leopard, who has implemented this in hopes of bringing unix behavior to samba shares, as like with nfs. In my mind, since unix level permissions were working fine with previous releases of samba, we're losing more than we're gaining with this improvement. Especially since with nfs, in example, I define my mount point and thus can create links on the share that point to local mount points and have them resolve. Most gui based operating systems, like OS X, have their own defined samba mount points; there is not a standard across operating systems. This makes making links inside the share that point to samba created mounts difficult. Regardless, this is a samba rant and not really a Leopard problem other than they are implementing what is standard in other Unix based os's.

On the flip side of this, yes, with unix extensions enabled, I've seen the links not resolve, then resolve, hours later, without explanation. That part is confusing.

diamondT · 11-11-2007, 06:08 PM

I don't get why on earth one would want to create a link in a shared folder (that is on a server) that points to a local file... it just makes no sense for me. Links on the server should stay/point on the server and links on the local machine should stay/point on the local machine.

In any case, I still think that this is a Leopard issue. Facts: a) it worked just fine with Tiger, b) it does work with Windows and c) it does work with other Linuxes (accessing the share from another linux works as expected).

And I did mention that in my case adding the forementioned option does not solve the problem

sonicbuddha · 11-11-2007, 06:24 PM

Again, its all a smb client issue. The reason why it worked on Tiger is that the client did not support unix extensions. This is probably the case for your Linux clients as well. And, yes, believe it or not, Windoze doesn't support it either. But then, thats not too surprising since Windoze doesn't have a concept of symlinks or unix permissions. You can check your smb version with a smb -V.

Have you tried mounting your share on your server? This was the big clue that it was the samba version when my Linux server performed the exact same way. Try setting "unix extensions = no" globally, not in a share.

As for why someone would want a link on a share to point to a local mount, well, thats default behavior for most other unix exported file systems. What I do, for example, is mount my exported volumes via nfs and then export a links tree that points to those volumes. When I move data between the volumes, all I have to do is change the link in the exported links tree and the moving of the data becomes transparent.

Ok, the old samba handling of links was neater than this, but it was unique to samba. I'm not one to defend it, in fact, I'm as annoyed as you, I'm just pointing it out.

diamondT · 11-11-2007, 07:41 PM

On second thoughts, for the links stuff I admit that when thinking of a shared home directory for example or the scenario you mentioned, yes it does make sense to allow for links to point to some local file...

Quote:

Originally Posted by sonicbuddha


	Try setting "unix extensions = no" globally, not in a share.

Yeap, that worked

Thanks! As for the security/permissions I don't really care

All my shares are read-only (my music and stuff like that...)

sonicbuddha · 11-11-2007, 07:54 PM

Glad you got it working!

A couple corrections to my post:

smbd -V (not smb -V)

And as for security, although the share appears to be owned by the person performing the mount, server side permissions are still respected. That was my bad. The following of links (which is what we were looking for) isn't very secure, though, allowing someone to create a link in their smb shared home directory to /etc/passwd on the server, for example, so as to access files the admin didn't intend on sharing.

A lot of people complain about this problem with unix extensions. It would be interesting to see if the samba team has a way of implementing unix extensions piecemeal, such as utilizing server side permissions and ownership while leaving the default behavior with symlinks.

10-28-2007, 10:13 PM	#1
diamondT Prospect Join Date: Feb 2005 Location: Toronto Posts: 25	Leopard and samba shares Hi, I have a couple of samba shares on a linux machine and I try to access them from Leopard/Finder. In these shares there exist some symbolic links. In Tiger everything worked just fine. But in Leopard, Finder tries to translate these links to the local filesystem, which of course results to the links being dead. Since I did not change my samba server settings and since everything was OK in Tiger I suspect this is a Leopard-specific prob. Any ideas? Tnx in advance.

10-28-2007, 10:25 PM	#2
CAlvarez Hall of Famer Join Date: Sep 2004 Location: Phoenix, AZ Posts: 4,975	Sorry, no ideas, except to say that I also have had a few issues with Linux Samba shares and Leopard for some time, no solutions. __________________ -- Carlos Alvarez, Phoenix, AZ "MacBook Nano" (Lenovo S10) Atom 1.6/2GB/160GB Mac OS X 10.5.6 Gigabyte Quad Core 2.83GHz Hackintosh 4GB/500GB Mac OS X 10.6 MacBook Air 1.8/2GB/64GB SSD http://www.televolve.com

10-30-2007, 03:28 PM	#5
MontyPython42 Registered User Join Date: Oct 2007 Posts: 1	CIFS Unix Extensions Leopard's SMB/CIFS supports the Unix Extensions, which include support for server-side symbolic links. I haven't yet figured out how to leave the Unix Extensions enabled while only disabling the symlinks (or making the SMB server handle them), but if you add Code: unix extensions = no to the server's smb.conf, that should fix the issue.

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10-30-2007, 12:23 AM	#3
sonicbuddha Prospect Join Date: Oct 2005 Posts: 9	I have this problem, too. I've tried troubleshooting by adding follow symlinks = yes to my smb.conf file (it should be active by default) with no results. Other than the symlinks that point outside the exported smb tree being broken, it the functionality seems normal. Although, honestly, this is an upgrade deal breaker for me.

10-30-2007, 05:07 PM	#6
diamondT Prospect Join Date: Feb 2005 Location: Toronto Posts: 25	Nope it doesn't I added "unix extensions = no" to smb.conf of the server, restarted the samba daemon, even restarted Leopard but the problem still exists... For the record, accessing the share from a windows machine works as expected. It seems more and more like a Leopard specific prob.

10-31-2007, 06:01 PM	#7
sonicbuddha Prospect Join Date: Oct 2005 Posts: 9	Ok, so I've done some troubleshooting. If I access the share utilizing smbclient, the links work as they are supposed to and resolve. If I attempt to mount the share using mount_smbfs and all I get is : # mount -t smbfs //<user>:@<server>/<share> <path to test mount point> mount_smbfs: failed to initialize the smb library: invalid argument Which might just be my usage. BUT, if I mount the share via the Finder and access the share via the command line through terminal, the links work as they are supposed to and resolve. Yet if I try to open a directory with the "open" command, the Finder fails. Trying to open files, on the other hand, succeed. Bottom line, this is a Finder issue.

10-31-2007, 06:26 PM	#8
BartVB Registered User Join Date: Oct 2007 Posts: 1	Same problems here. Haven't tried resolving this yet but I did notice that those symlinks did work yesterday. No idea what was different then. I certainly didn't change anything on the Samba side (Debian Lenny machine) and normally I connect with cmd-k and the URL smb://192.168.1.1/storage As I said, no idea why this worked yesterday but doesn't work today. It sure is an indication that this is some kind of fluke on the Leopard side.

11-11-2007, 06:08 PM	#10
diamondT Prospect Join Date: Feb 2005 Location: Toronto Posts: 25	I don't get why on earth one would want to create a link in a shared folder (that is on a server) that points to a local file... it just makes no sense for me. Links on the server should stay/point on the server and links on the local machine should stay/point on the local machine. In any case, I still think that this is a Leopard issue. Facts: a) it worked just fine with Tiger, b) it does work with Windows and c) it does work with other Linuxes (accessing the share from another linux works as expected). And I did mention that in my case adding the forementioned option does not solve the problem

11-11-2007, 06:24 PM	#11
sonicbuddha Prospect Join Date: Oct 2005 Posts: 9	Again, its all a smb client issue. The reason why it worked on Tiger is that the client did not support unix extensions. This is probably the case for your Linux clients as well. And, yes, believe it or not, Windoze doesn't support it either. But then, thats not too surprising since Windoze doesn't have a concept of symlinks or unix permissions. You can check your smb version with a smb -V. Have you tried mounting your share on your server? This was the big clue that it was the samba version when my Linux server performed the exact same way. Try setting "unix extensions = no" globally, not in a share. As for why someone would want a link on a share to point to a local mount, well, thats default behavior for most other unix exported file systems. What I do, for example, is mount my exported volumes via nfs and then export a links tree that points to those volumes. When I move data between the volumes, all I have to do is change the link in the exported links tree and the moving of the data becomes transparent. Ok, the old samba handling of links was neater than this, but it was unique to samba. I'm not one to defend it, in fact, I'm as annoyed as you, I'm just pointing it out.

11-11-2007, 07:54 PM	#13
sonicbuddha Prospect Join Date: Oct 2005 Posts: 9	Glad you got it working! A couple corrections to my post: smbd -V (not smb -V) And as for security, although the share appears to be owned by the person performing the mount, server side permissions are still respected. That was my bad. The following of links (which is what we were looking for) isn't very secure, though, allowing someone to create a link in their smb shared home directory to /etc/passwd on the server, for example, so as to access files the admin didn't intend on sharing. A lot of people complain about this problem with unix extensions. It would be interesting to see if the samba team has a way of implementing unix extensions piecemeal, such as utilizing server side permissions and ownership while leaving the default behavior with symlinks.