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After backup: Destination is read-only?
I'm working on implementing a proper backup procedure as most experts on this forum recommend. But when trying to backup a large amount of data, I keep getting this error message:
Backup: Error backup job 'data to USB_HDD_4': destination is read-only.
The data, at first glance, seems to be copied to the USB drive.
I tried this on 3 different disks, 2 of which brand-new out of the box. So I don't believe they would all be faulty. This makes me think it is either a problem with my data on the NAS or a problem in the FrontView backup procedure.
When I connect the disk to the PC and remove directories manually, for some files with exteremely long names and a deep path, I get an error message "Source Path Too Long":
Therefore I'm currently suspecting very long file names and/or very long file paths, but I'm not sure if that is really what is causing this.
I removed some directories I suspected from the NAS, but in the next backup, the message keeps comming back. So now I'm stuck in a catch-22 situation. I'm not sure if my backup succeeds and don't want to remove any more data from the NAS, because it may not have been backed up properly. So I'm not able to implement a proper backup procedure at this time.
Has anyone found a root cause for the "Destination is read-only" message?
Is there any way that I can get more information on what went wrong during the backup (e.g. what file is causing the message)?
Backup: Error backup job 'data to USB_HDD_4': destination is read-only.
The data, at first glance, seems to be copied to the USB drive.
I tried this on 3 different disks, 2 of which brand-new out of the box. So I don't believe they would all be faulty. This makes me think it is either a problem with my data on the NAS or a problem in the FrontView backup procedure.
When I connect the disk to the PC and remove directories manually, for some files with exteremely long names and a deep path, I get an error message "Source Path Too Long":
Therefore I'm currently suspecting very long file names and/or very long file paths, but I'm not sure if that is really what is causing this.
I removed some directories I suspected from the NAS, but in the next backup, the message keeps comming back. So now I'm stuck in a catch-22 situation. I'm not sure if my backup succeeds and don't want to remove any more data from the NAS, because it may not have been backed up properly. So I'm not able to implement a proper backup procedure at this time.
Has anyone found a root cause for the "Destination is read-only" message?
Is there any way that I can get more information on what went wrong during the backup (e.g. what file is causing the message)?
Have been looking for a solution for this problem for a long time, but never managed to find the root cause.
In the end, I decided to remove the offending subdirectory that contained a file backup of a Windows system. This solved the problem with the backup procedure.
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- how is the disk formatted?
StephenB wrote: how is the disk formatted?
They are all NTFS formatted. The two new disks came pre-formatted NTFS out of the box.- Try putting them in a windows system and if windows wants to scan/fix let it.
- Yes, did that with every disk and the scan/fix (chkdsk) will fix system file errors if they exist. And after that, I can switch off the read-only bit on the affected directory. But that still doesn't ensure me if the backup is complete and valid. And next time I do another full backup on the disk of the same data, the problem occurs again. So I'm first trying to figure out what is causing the read-only to be set in the first place, so I can find a way around it.
The logs in FrontView only offer one line of error message: "Backup: Error backup job 'data to USB_HDD_4': destination is read-only". But there I cannot find any root cause. This makes me distrust the whole quality of the backup. And if I cannot trust the quality of the backup, I cannot implement a proper backup procedure either, what is my goal to begin with and is strongly recommended here.
Is there a way to figure out which file(s) on my NAS would cause the read-only flag to be set on the external NTFS disk, in order to get to the root cause of this problem? - The most likely cause of that error is that the "dirty" bit is set on the disk volume. Windows scan/fix should reset that.
The dirty bit is often set when the disk is not ejected before removal, or if the NAS sees some other issue when mounting it.
I back up over over the network, and not to local disks - so I don't have direct experience on how often this occurs. StephenB wrote: The most likely cause of that error is that the "dirty" bit is set on the disk volume. Windows scan/fix should reset that.
The dirty bit is often set when the disk is not ejected before removal, or if the NAS sees some other issue when mounting it.
I back up over the network, and not to local disks - so I don't have direct experience on how often this occurs.
I have adopted a strict "always eject first" policy ever since USB external disks and memory sticks became available and use the same approach when connecting via USB directly on the NAS. I use the Eject button always. So that can't be it.
I do a chkdsk on Windows first to make sure there are no problems with the drive. Windows tells me that the disk is OK. If the NAS sees a problem when I connect it there, there should at least be some hint on what is wrong in the logs.
I tried backing up via the network also, but with > 4 TB that takes forever and the network speed seems to decline the longer into the backup I get. So for me that's not an option.
So this brings me back to my initial point: "This makes me think it is either a problem with my data on the NAS or a problem in the FrontView backup procedure". But still not closer to finding out what is at the hart of this problem.
Has anyone found a root cause for the "Destination is read-only" message?
Is there any way that I can get more information on what went wrong during the backup (e.g. what file is causing the message)?- I still suspect the dirty bit somehow got set. If it happens again, try writing a file to the drive manually and see if that works. If it is mounted read-only then it will fail.
USB backup is reasonably fast on the 516, but it should be just as fast to back up over a gigabit network. USB 3.0 would be faster over the network. Speeds are here: http://www.smallnetbuilder.com/nas/nas- ... l=&start=1 StephenB wrote: I still suspect the dirty bit somehow got set. If it happens again, try writing a file to the drive manually and see if that works. If it is mounted read-only then it will fail.
Yes, I'm not arguing that. But I would like to find the reason for the dirty bit to be set. If verified that all directories are read/write before I connect it to the NAS. Might be onto something with the long path and file names. Just started splitting up the backup, with one backup task for each share. Two smaller ones have succeeded sofar. I now scheduled the other shares, except the share where I suppect the long file names and paths reside. Will try to pin that down some more, if all the other shares have succeeded. Will take a while before everything is copied though, so more on that tommorow.StephenB wrote: USB backup is reasonably fast on the 516, but it should be just as fast to back up over a gigabit network. USB 3.0 would be faster over the network. Speeds are here: http://www.smallnetbuilder.com/nas/nas- ... l=&start=1
Would think so too, but can't achieve it in my setup. What would take 8 hours on a disk connected directly to the NAS, takes over 23 hours when copying over the network from the NAS to a USB disk on the PC. Can't really explain why this is so slow.- Have narrowed it down to my "Documents" share that is causing the problem. All the other shares backup without issues. Will try to narrow it down further in the coming period.
If I connect the disk to the PC and look for files and dirs with read-only attribute set, it finds nothing. Strange. The NAS just told me there is a read-only problem.F:\>dir /A:R /R *.*
De volumenaam van station F is My Disk
Het volumenummer is XXXC-487P
Map van F:\
Het bestand is niet gevonden (= file not found)
If I check for dirty bit, it tells me the disk is clean.F:\>fsutil dirty query f:
Volume - f: is schoon (= f: is NOT dirty)
If I do a check disk on the drive, it tells me that no problems were found.
We've been having these issues since the original OS6 and it's only on NAS drives were the USB drive is unplugged after backing up.
We have a numbe rof customers who rotate between two or more USB backups and even when you select 'Eject after backup' every few weeks this problem occurs.
Customers with only one drive that is permenantly connected have never had this issue, so it's a bug in the software or hardware.
In most cases, if you mount the drive in a PC and let the OS "repair" it, the drive becomes readable again.
Usually what is happening is that the dirty bit is being set on the drive.
Have been looking for a solution for this problem for a long time, but never managed to find the root cause.
In the end, I decided to remove the offending subdirectory that contained a file backup of a Windows system. This solved the problem with the backup procedure.
Sadly, I wish that was the case for our customers! We've now tried reformatting the backup drives as NTFS and HFS+ but the problem always comes back at some point.
Netgear still have problems using USB external drives and backup, which after nearly 2 years, needs fixing.
I had similar issues trying to back up a shared network drive to another netwrok drive that only I could see. After the initial backup it would ofcourse only update the changes. After a recent update to the newest software for the shared NAS the back up function stopped working.
"destination is read-only or files/folders could not be created. Check if these files or folders meet the destination file system limitation."
The destination is not read only. I unmounted the drives and hooked them up directly to my PC and scanned the file system with that.....blah blah blah. I tried a ton of different things before I finally just renamed the old back up folder and created a new empty one. The next backup then repopulated this new folder and everything works fine. Subsequent back ups have ran fine as well. I don't know if anyone else will find this helpful but it worked for me.
On a side note, I would be curious to hear an explanation for why this problem even occurred. Why would an update cause the system to erroneously identify a file as read only?
The status info stored on the drive includes a "dirty' bit, which usually ends up set if if the disk is not properly dismounted - esp. if a file copy was in progress when that was done.
If it is set (for whatever reason), the volume is mounted read-only by the NAS. On Windows, it results in a scan/repair prompt.
Clearing the dirty bit generally is only done as part of a scan/repair process that ensures the NTFS structures are ok. The NAS doesn't have the ability to do that, so you need to connect the drive to a system that can do it.
Your situation with the backup might have had a different cause of course.
- Can you send me your logs (see the Sending Logs) link in my sig?
Do you still have this issue if you connect the USB disk to the front USB port on the NAS?
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