I'm trying to set up the Exact Mirror mode to actually mirror everything from the left to the right on the filesystem level, exactly. However, I ran into two issues with reparse points. They both seem to affect junctions, file and folder symlinks in the same way, although I haven't tested every permutation.
1. Metadata changes are ignored when comparing reparse points
After mirroring a folder containing all kinds of reparse points, I update the modified timestamps, set a read-only flag or something else on the reparse points in the source. Then I rerun the profile, but no changes are detected, even though these changes would be detected for regular files and folders to trigger an update of the respective attributes on the destination side.
2. Converting reparse points to or from any other kind of directory entry is not possible
After mirroring a folder containing all kinds of reparse points, I delete everything in the source and recreate the entries with regular files and folders (i. e. all names included are the same, but file symlinks are now regular files and folder symlinks or junctions are now regular folders). Rerunning the profile detects differences between the source and destination, but it can't actually replace the reparse points in the destination with regular entries from the source. So, nothing changes and the next run will detect the same differences again.
I'm not sure if there is still an option I overlooked or misconfigured, so just in case someone wants to take a look, I have exported and attached the profile I use for evaluating. It's the closest approximation to my goal I could come up with so far, although I'm not sure if I will enable updating security metadata for existing items after all.
Note that this is not an exercise trying to find exotic configurations that fail, but are actual changes that happen intentionally from time to time on my system and I would like to reflect them when updating my backup with a sync method. For example, I sometimes move folders from one place to another but create junctions in their original locations, pointing to the respective new locations. At the moment, I can't find a way to replicate this with Syncovery (or any other software I've tried so far properly, to be fair). This looks like a very promising product with some great features though, so I'd very much like to use it in the future (the hard link support is, from all I know, a pretty unique selling point for example).
Exact Mirror mode and reparse point problems
Exact Mirror mode and reparse point problems
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- test.zip
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Re: Exact Mirror mode and reparse point problems
Hello,
thanks, that's very interesting. It doesn't sound too hard to implement these two items. I will check it.
thanks, that's very interesting. It doesn't sound too hard to implement these two items. I will check it.
Re: Exact Mirror mode and reparse point problems
I purchased Syncovery Premium a while ago and gave this another try today, with version 11.14.3. I'm only using local NTFS filesystems. The current state is this:
1. Metadata changes are unfortunately still not detected and therefore continue to reside only on the source.
2. I'm not sure if this changed in Syncovery or if I'm simply not testing in the same way, but if I replace a junction with a folder of the same name in the source, the mirror will then detect changes. However, it will still not replace the junction in the target with a folder. Instead, it replaces the contents of the target junction with the contents of the source folder. The same applies to file symlinks.
2a. This isn't about reparse points, but it might be related to 2. If I have a file that has been mirrored and replace it with a folder of the same name in the source, it will delete the file from the target but will not create the new folder in one go. A second run will fix this, though - so not really a big deal. Just wanted to mention it as well. The reverse works fine, i. e. replacing a folder with a file will make Syncovery delete the folder from the target and copy the file from source all in one mirror.
I think I can still use it for a couple of other jobs, although I need to pay close attention to the changes overview. 2 can be potentially dangerous if the reparse points are defined with absolute paths.
1. Metadata changes are unfortunately still not detected and therefore continue to reside only on the source.
2. I'm not sure if this changed in Syncovery or if I'm simply not testing in the same way, but if I replace a junction with a folder of the same name in the source, the mirror will then detect changes. However, it will still not replace the junction in the target with a folder. Instead, it replaces the contents of the target junction with the contents of the source folder. The same applies to file symlinks.
2a. This isn't about reparse points, but it might be related to 2. If I have a file that has been mirrored and replace it with a folder of the same name in the source, it will delete the file from the target but will not create the new folder in one go. A second run will fix this, though - so not really a big deal. Just wanted to mention it as well. The reverse works fine, i. e. replacing a folder with a file will make Syncovery delete the folder from the target and copy the file from source all in one mirror.
I think I can still use it for a couple of other jobs, although I need to pay close attention to the changes overview. 2 can be potentially dangerous if the reparse points are defined with absolute paths.