Converting Macintosh Files

[Lisa Parris]

Hi. Please bear with me as I don't know very much about Macintoshes.

We have have several servers in our organization. Most of our clients are
using Windows XP but we have three users in our creative department using
Macintosh OS X.

For many years we were running Services for Macinotsh on our "creative"
server. We just installed a new server and had to intention of eliminating
SFM and having the clients connect via SMB. When we moved the data from the
old server to the new one, the files lost all their "resource forks" , etc.
and the users can't get their files to work properly connecting via SMB

So, I guess the questions are 1) Is this to be expected or did we somehow
move the data over the wrong way? And if so, how should we have gone about
it 2) Assuming the answer to #1 is that this is to be expected, is there
some utility or some way for us to convert the files so that the resource
info is "attached" to the file?

We need to get rid of SFM for a variety of reasons, mainly because we'd
using some software that's not compatible with it in our disaster recovery
infrastructure.

Thanks in advance,

Lisa

 

[William Smith]

Hi. Please bear with me as I don't know very much about Macintoshes.

We have have several servers in our organization. Most of our clients are
using Windows XP but we have three users in our creative department using
Macintosh OS X.

For many years we were running Services for Macinotsh on our "creative"
server. We just installed a new server and had to intention of eliminating
SFM and having the clients connect via SMB. When we moved the data from the
old server to the new one, the files lost all their "resource forks" , etc.
and the users can't get their files to work properly connecting via SMB

So, I guess the questions are 1) Is this to be expected or did we somehow
move the data over the wrong way? And if so, how should we have gone about
it 2) Assuming the answer to #1 is that this is to be expected, is there
some utility or some way for us to convert the files so that the resource
info is "attached" to the file?

We need to get rid of SFM for a variety of reasons, mainly because we'd
using some software that's not compatible with it in our disaster recovery
infrastructure.

Hi Lisa!

Your Mac files may not have lost their resource forks. If you copied the
files from one NTFS partition to another (not FAT or FAT32) then you
probably still have the resource forks. However, when you connect via
SMB, your Mac won't be able to see the resource forks. SMB doesn't
support them.

Mac OS X works around this issue by splitting the resource fork and the
data fork prior to copying files to the server. The data is in the file
with the same name but the resource information is store in
"._filename". If you've copied any files to the server via SMB then your
Windows users are probably noticing these files.

While Mac OS X's SMB is good for getting the occasional file from a Mac
to a Windows user, it's not a very robust and can cause strange
permissions issue such as the inability to delete or rename files, etc.

If you have relatively few Macs then I'd recommend using Dave or
ADmitMac from <http://www.thursby.com>. These are much better SMB
clients.

Or if you have several Macs then I'd recommend a better AFP server
solution such as ExtremeZ-IP from <http://www.group.logic.com>. I don't
understand how SFM can impede a disaster recovery plan of any type. Can
you elaborate on what you mean by this?

Hope this helps! bill

 

[Lisa Parris]

Hi William,

Part of our Disaster Recovery plan depends on Microsoft's Data Protection
Manager which is basically a product that replicates files and changes to
files over the network on a nearly continuous basis. The only data we're
having trouble with is the Macintosh data that's stored on the one server
that's running SFM.

Microsoft says that the Macintosh data may contain "alternate streams" which
could be causing a problem. Not to sound like an idiot but I don't know
exactly what that means (is that related to forks?). We're having problems
with really long filenames and filenames that have unsupported characters
among other things. If I'm understanding correctly, which I'm probably not,
you're saying that for each Macintosh file on the network, there's a hidden
(or not hidden) file "._filename" which corresponds to it?

Thanks for the reply and any additional help you can give me!

 

[Paul Harman]

Mac OS X works around this issue by splitting the resource fork and the
data fork prior to copying files to the server. The data is in the file
with the same name but the resource information is store in
"._filename". If you've copied any files to the server via SMB then your
Windows users are probably noticing these files.

I've got a related issue.

I've got a PC application that needs to fake the creation of resource forks,
sharing out to Macs. After a lot of digging I've managed to get this to work
if the sharing is via SFM, by fiddling with the NTFS alternate file streams
for the file.

I /can't/ get it to work if the share is via SMB. I'm creating the "dot
underscore" files and sticking the resource forks [or, rather, the
AppleDouble data] in, but the Mac refuses to recognise that there's a
resource fork there.

Any ideas?

Paul

 

[Rod Dorman]

...
Microsoft says that the Macintosh data may contain "alternate
streams" which could be causing a problem. Not to sound like an idiot
but I don't know exactly what that means (is that related to forks?).

Yes. SFM uses NTFS alternate data streams to store the resource fork
and the finder info.

see http://tinyurl.com/s8es for details.

 

[William Smith]

Hi William,

Part of our Disaster Recovery plan depends on Microsoft's Data Protection
Manager which is basically a product that replicates files and changes to
files over the network on a nearly continuous basis. The only data we're
having trouble with is the Macintosh data that's stored on the one server
that's running SFM.

Microsoft says that the Macintosh data may contain "alternate streams" which
could be causing a problem. Not to sound like an idiot but I don't know
exactly what that means (is that related to forks?). We're having problems
with really long filenames and filenames that have unsupported characters
among other things. If I'm understanding correctly, which I'm probably not,
you're saying that for each Macintosh file on the network, there's a hidden
(or not hidden) file "._filename" which corresponds to it?

Thanks for the reply and any additional help you can give me!

Hi Lisa!

I'm completely unfamiliar with Microsoft's Data Protection Manager but
it does have a newsgroup where you may want to ask about Mac files
microsoft.public.dataprotectionmanager.

Although Mac files do use alternate streams to store the resource fork
information as Rod points out in his response to you, I find it
difficult to believe that they aren't supported. Macs aren't the only
users of multiple streams. It's hardly data protection if it doesn't
protect all data.

The AFP version on Windows server is 2.2, which doesn't support file
names longer than 31 characters. The ExtremeZ-IP server software uses
AFP 3.2, which not only supports the 254 character maximum but also
supports Mac OS X 10.4 (Tiger) Access Control Lists (ACLs).

You're correct that for every file your Macs place on the server when
connected via SMB that there will be an additional "._" file. Depending
on your Windows settings, hidden files may be set to be shown and these
files will propagate to the top of the file list because of their names.
These files don't exist when Macs connect via AFP, but instead that
information gets put into the alternate data stream.

Hope this helps! bill

 

[Paul Nelson]

Some additional notes:

1) William is correct - Apple's use of SMB does not recognize the defacto
standard method of storing resource forks the way Microsoft, Thursby,
ExtremeZ do. If you have a lot of data in the original Microsoft SFM
format, you are probably better off using a third party solution.

2) That said, I would bet that your problem is related to file names as much
as resource forks. William is correct again that the streams used in
Macintosh files are not any different that ones used by Microsoft Office.
It should not matter to Data Protection Manager, but it might. File names
with characters that Mac users love (like slashes, bullets) often drive
Windows software nuts. Even with a third party product, you may continue to
have problems with existing products, because these products don't rename
files that already exist. You might benefit from using a program that will
scan your file system and rename files that have funny characters in them.

3) If you get an evaluation of DAVE, Thursby's support department should be
able to help you identify and correct problems with Data Protection Manager.

Paul Nelson
Thursby Software Systems, Inc.