Ubuntu 10.04: Sharing a Folder on an NTFS Partition

I had two computers running Ubuntu 10.04.  These machines were connected by ethernet cable through a router.  Both had Samba installed, and both had a shared folder set up as described in another post.  I had set up one of those shared folders on an ext3 partition.  As that other post indicates, I was able to see the contents of that shared folder from the other computer.  But without thinking about it, I had set up the other computer's shared folder on an NTFS partition.  Seeing a folder on that partition turned out to be a more complicated matter than I had expected.  This post describes my efforts in that regard.

Right away, I rediscovered that chown wouldn't work as expected with NTFS drives, and that it was therefore necessary or advisable to type "sudo gedit /etc/fstab" and change the lines for NTFS drives or partitions to something like this:

UUID=[UUID for the drive] /media/partitionname ntfs-3g rw,suid,dev,exec,auto,user,async,umask=000 0 0

and then unmount ("sudo umount /media/partitionname") and remount the partition.  Remounting would apparently force a look at the new contents of fstab, and could be done with "sudo mount /dev/sdc3 /media/drive1" or just "sudo mount -a" (assuming a folder named /media/drive1 had already been created (e.g., "sudo mkdir /media/drive1")).  That fstab line was one I had developed to replace the "defaults" word that appeared in some fstab lines previously:  it made all of the default settings explicit, and changed some of them.  Yet even with this change, when I tried to set the Sharing Options in Nautilus, I got this error message:

Folder Sharing

'net usershare' returned error 255: net usershare add: cannot share path /media/partitionname/folder2 as we are restricted to only sharing directories we own.

Ask the administrator to add the line "usershare owner only=false" to the [global] section of the smb.conf to allow this.

I was willing to go into smb.conf and make that change, but first I wanted to know why (as I confirmed with a right-click > Properties) root still owned that folder.  This led to the insight that NTFS filesystems (such as the one I was trying to share) did not remember ownership, so the partition would need to be reminded each time I mounted it.  One way to do this was to modify the fstab line to include user and group identifications:

UUID=[UUID for the drive] /media/partitionname ntfs-3g rw,suid,dev,exec,auto,user,async,umask=000,uid=username,gid=groupname 0 0

and then save fstab and unmount and remount the partition (above).  And yet that still didn't do it.  The better statement seemed to be, not that NTFS partitions needed to be reminded, but that they simply didn't have an ownership concept.  There seemed, then, to be no alternative but to type "sudo gedit /etc/samba/smb.conf" and add the line "usershare owner only=false" to its [global] section, as advised above.  I saved and closed that and tried Sharing Options again.  This time it worked, or at least it didn't give me an error message.

Unfortunately, the shared folder still wasn't showing up on the other computer's Places > Network list.  It sounded like the solution might be to try Sharing Options as root ("sudo nautilus").  Unfortunately, at this point "sudo nautilus" was giving me an error message on that computer:

(nautilus:23890): Unique-DBus-WARNING **: Error while sending message: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.

I wondered what would happen if I stepped away from the NTFS situation for a moment.  I decided to try sharing a folder on an ext3 partition in that same computer.  I right-clicked on the ext3 partition in Nautilus, chose Create Folder, named the folder, went to the Share tab, and selected "Share this folder" and "Allow others to create and delete files in this folder."  This gave me an error message:

'net usershare' returned error 255: net usershare add:
cannot stat path /media/partitionname/foldername to ensure this is a directory.  Error was No such file or directory

I guessed that this might be because I had gone directly to the Share tab without first clicking Close in the Basic tab there in the P4 Share Properties dialog.  So, OK, I saved the new folder first, and then right-clicked on it in Nautilus and chose Sharing Options.  This time it went OK.  I went into System > Administration > Samba, as described in the other post, and added this folder there.  But I still wasn't able to see it from the other computer.  I rebooted this problematic machine and tried again.  In doing so, I noticed that GParted and some other things were still running on another desktop, so that may have explained why "sudo nautilus" worked OK after the reboot.  The sharing step just described also worked OK.  But Places > Network on the other computer still didn't show the problematic computer.  

I was just about to change some hardware and reinstall Ubuntu on that machine anyway, so I deferred further effort on this project until after that was done.  At that point, though, I found a better folder-sharing solution by using a Synology network-attached storage (NAS) unit.

Ubuntu 10.04: "rsync: failed to set permissions on [folder]: Operation not permitted" -- and Beyond Compare

Using rsync to automate backups on Ubuntu 10.04 (Lucid Lynx), I got a million iterations of this message:  "rsync: failed to set permissions on [target drive & folder]: Operation not permitted."

I had previously had a somewhat similar problem with an external USB drive.  The solution there had been to reformat the drive.  I didn't want to have to do that again if it wasn't necessary.  I ran a search and, following what i understood from one post, I set out to change ownership on the target folder so as to match the ownership of the source folder.  To do that, I went into Ubuntu's Terminal and typed "sudo nautilus," and then navigated Nautilus to File System/media/[target drive].  (It could instead have been in File System/mnt/.)  I right-clicked on that and got Properties > Permissions.  The owner was root.  When I tried to change it, it changed back.

I exited Nautilus and followed instructions in Ubuntu Community Documentation, combined with advice from another post and the Ubuntu manual page for chown.  I typed "sudo chown -R ray /media/[target drive]."  That ran for five or ten minutes, as the chown (change ownership) command recursed (i.e., -R) all of the subdirectories on the target drive.  But that, by itself, did not fix the problem; indeed, it didn't seem to change anything.  Root was still the owner of the target drive.  Then again, the properties of the target allowed others to create and delete files as well, so why was rsync complaining?

There appeared to be another way.  In Terminal, I typed "sudo gedit /etc/fstab."  I already had a line for the target drive, which I'll call simply TARGET.  That line was as follows:

UUID=[UUID for the drive] /media/TARGET ntfs-3g defaults,umask=000 0 0

The Ubuntu documentation I was now looking at said, "Permissions are set at the time of mounting the partition with umask, dmask, and fmask and can not be changed with commands such as chown or chmod."  So possibly that's why my chown command wasn't doing anything.  Following the advice, I changed it to dmask=027,fmask=137, since this was going to be just a backup drive anyway.  I also saw that "defaults" meant these options:  rw,suid,dev,exec,auto,nouser,async.  All of those were fine, as far as I knew, except for this information from the documentation:

user - Permit any user to mount the filesystem. This automatically implies noexec, nosuid,nodev unless overridden.

nouser - Only permit root to mount the filesystem. This is also a default setting.

I wanted user, not nouser.  I decided it might be easier to spot this sort of thing, in future visits to fstab, if I just changed all occurrences of "defaults" to make these options explicit.  Besides, in light of the statements just quoted, it seemed that I would have to override several defaults anyway.  So the resulting fstab line looked like this:

UUID=[UUID for the drive] /media/TARGET ntfs-3g rw,suid,dev,exec,auto,user,async,dmask=027,fmask=137 0 0

I saved fstab and, in Terminal, typed "sudo mount -a" to mount the partitions according to these new instructions.  Then I ran the rsync command again.  Sadly, these changes made no visible difference.  I still got a million error messages.  So, OK.  I had been overlooking the first three error lines in the log output of my rsync command.  The second and third lines followed the pattern of this first line, but were for subdirectories:

rsync: failed to set times on /media/TARGET/.": Operation not permitted (1)

I hadn't previously investigated the "failed to set times" error, so now I did.  What I got out of the forums I came across was that possibly I had a syntax error in my rsync command.  Here's how it went:

rsync -qhlEtrip --progress --delete-after --ignore-errors --force --exclude=/.Trash-0 --exclude=/.Trash-1000/ --exclude=/lost+found/ /media/SOURCE /media/TARGET 2> /media/SOURCE/Backuplog.log

This was identical to the perfectly working rsync command that I was occasionally using to back up SOURCE to a different partition, with one exception:  in the one shown above, I didn't have a slash after Trash-0.  So I changed that to --exclude=/.Trash-0/ and re-ran it.  That didn't solve it.  I then noticed (I was using two desktops) that I had gotten a message telling me that the system was not able to mount the partition:  "Device or resource busy."  So possibly that fstab step still needed to be tested.  I rebooted the system.  None of the the parittions that I had adjusted in fstab were mounted.  I went back, deleted the dmask and fmask parts, and returned it to umask=000, and rebooted.  Now the partitions were all mounted.  I ran the rsync command again.  The problem had not changed.

I found an informative thread in which bscbrit suggested trying to use cp to copy a single file from the source partition to the target partition.  If it worked, s/he said, the problem was not with permissions; it was just with trying to use rsync.  So in SOURCE I copied a file, renamed it "x.txt," and typed "cp /media/SOURCE/x.txt /media/TARGET," and it worked:  there was a copy of x.txt on TARGET.  It sounded like there could be a kind of mismatch between the ext3 source drive and the ntfs target.  I also came across an informative post by djgrandmarquis that said rsync could have problems with Windows file systems.  That was in response to a question about very slow backup times, which  I had also experienced.  I needed Windows file systems because I was backing up to an offsite drive that I sometimes shared with a Windows system.

I had previously investigated Beyond Compare (BC) as another way of synchronizing drives.  BC had drawn  a lot of praise.  Since my previous writeup, I had bought a copy and had been using it for several months on Ubuntu, WinXP, and Linux.  I had subsequently found a comparison of many such programs; but since I had already bought BC and was using it with good results, I didn't explore that comparison.  I could verify that BC was fast and trouble-free when compared to rsync, especially when going between ext3 and ntfs drives.  I also liked the visible information about what was being changed and backed up.  So I decided to stop using rsync and start relying only on BC for my backups.

There were a few differences between the Windows and Linux versions of BC; but in an impressively thorough reply to my post, Craig from BC said that the portable version of BC ran well on Wine in Ubuntu.  I had already installed Wine, and I had also already been using the portable version of BC3; I preferred portable versions to save time during reinstallations, as I was able to save them elsewhere than drive C and therefore they weren't wiped out during a Windows reinstall.  So to try this out, I copied over the BC3 portable installation and tried using a funky procedure involving PortableApps to try the Windows version.  But now it seemed I had not properly understood or used that procedure:  PortableApps now appeared to be looking, not for .exe files, but for ".paf exe" files.  Meanwhile, it looked like Beyond Compare 3 would run fairly well under Wine, so I gave it a try.  Following the steps described in that previous post, in Terminal I navigated to the folder where I had the original BC installer, typed "ls" to get the exact filename, and typed "wine BCompare-3.1.10.11626.exe" to install that file.  Terminal reported some "fixme" and "err" messages; nonetheless, the Beyond Compare 3 Setup Wizard ran.  I had a licensed version, so I entered the license key, and followed the instruction to restart.  It worked, but now I came to the new realization that Windows identifies drives by letter (C: etc.), while Ubuntu identifies them by name (/media/DATA, etc.).  So of course a Windows version of Beyond Compare, looking for Windows-type folder paths, running in Ubuntu, is going to find only a limited number of Ubuntu locations.  I didn't pursue that problem.

This left at least one issue unresolved.  While I was OK with doing manual comparisons for now, I was still not at the point of being able to write scripts to automate BC backup processes.  I started another post on that.