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According to this blog post:

 

http://blog.covecube.com/2013/11/stablebit-drivepool-2-1-0-432-beta-reparse-points/

 

DrivePool supports reparse points but it DOESN'T appear to support Hard Links.  I'm thinking that this is the reason that Plex can't host its media database on the pool (which isn't working for me and, according to the comments on the blog post, doesn't work for anyone else).

 

Is there any plans to implement Hard Links for the pool?  Is there any workaround to this?

 

Thanks!

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Because of the nature of Hard Links I doubt that DrivePool will ever really support them. They are an NTFS filesystem construct to create multiple pointers in the filesystem index to the same file on a drive. Directory junctions and symbolic links operate on a different level. I'm sure someone can chime in with a more detailed explanation, but basically one is like street address that the post office (drivepool) can intercept and forward to a different address and the other is more like GPS coordinates that are fixed. That's a pretty weak comparison, but I think it hits the general idea.

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Actually, Alex does mention this in the post:
 

Hard Links
In addition to the other types of links, the Link Shell Extension has the ability to create Hard Links. Hard Links are not implemented using reparse points and so this build of StableBit DrivePool does not support them. Hard Links are implemented directly in NTFS and can only point to a file on the same volume.

 

That last bit is the key here. "Same volume". While the Pool is a single volume, the disks that make it up are not. And because hard links are handled in a different way than reparse points, it makes it that much harder to support.

 

Thought to use the mail analogy, reparse points are like a "change of address" form. Hard Links is like being friends with the mail carrier, and getting him to deliver your mail to a different address. DrivePool can talk to the bureaucracy, but not with the mail carrier.  I hope that makes more sense.

 

I've also flagged this discussion for Alex, so he can clarify.

 

 

 

Also, Plex doesn't appear to use any sort of file system linking, so there shouldn't be any issue here.

If you could enable file system logging and see if you can reproduce any errors?

http://wiki.covecube.com/StableBit_DrivePool_2.x_Log_Collection

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According to the Plex team they DO use some sort of linking tech:

 

"What sort of drive did you put the content on? Is it perhaps something using drive-spanning? Some drive-spanning implementations apparently have trouble with symlinks/hardlinks, which are required by Plex Media Server for the metadata. There are also some filesystems that have trouble with (or don't support) them, so you might want to check the filesystem if you're not using NTFS for the drive."

 

They also said:

 

"I've never actually heard of this sort of thing described as "reparse points". Interesting. Anyway, I believe that the metadata bundles do use hardlinks as you mentioned."

 

So it looks like hard links might be as play here.  Is there a command to check for them? 

 

As soon as I moved my plex data folder off the pool everything worked correctly so there must be something going on here. 

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Looks like I spoke to soon. When I checked previously, I didn't see any links. 

 

 

Could you link the thread.

 

Also.... symlinks and hard links are two entirely different link types. And Symlinks are a type of "reparse" point.

http://en.wikipedia.org/wiki/NTFS_reparse_point

Even Microsoft calls symlinks and junctions and other links "Reparse Points". 

 

SoI really, really hope that wasn't the developers that was saying that. If it was, that's .... scary. 

 

 

 

Coincidentally, I installed plex last night.... 

I checked the metadata files. And yes, the metadata is using hardlinks. Specifically the images. You can check on the specific file using "fsutil hardlink list" on the individual files... or there are some shell extensions that will show you.

But not all the images. Apparently where I quickly looked is where they don't use hardlinks at all. So I must apologize for the incorrect information.

 

 

So unfortunately, no we don't support Plex Metadata on the pool. At all. We may add Hardlink support in the future, but considering how hard it was to implement reparse point support... and the vast differences and requirements for hard links.... it may not be for a while.

 

 

To be honest, I'm shocked and horrified that they'd use hardlinks like this. They maintain a SQLite database. Wouldn't it be much more elegant, efficient and compatible to just "dump" the images in a folder, and then link to those folders for the content (this is what XMBC does, actually)?

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I'm happy to link to the thread:

 

https://forums.plex.tv/index.php/topic/114192-metadata-images-not-loading/

 

I'm wondering if it's possible to make a note that Plex Metadata store is not supported on the pool.  It'll help save people time if they decide to move things (if you have a large library it can take HOURS to move over). 

 

Thanks for the help.

 

PS: I don't believe I was speaking with a developer. 

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Apparently, I can't view that thread. Even after logging in.

 

 

At best, we could add it to the FAQ. Having it notify you in DrivePool would be problematic.

 

And ironically, if they used XBMC's approach and did all this linking in their database instead on the file system, there wouldn't be an issue at all.

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Thanks for this thread. I ran into this issue with Plex and Drivepool and had a hunch it was due to Drivepool.

It's unfortunate that this was never put into the FAQ and I had to find out the hard way after spending 12+ hours moving my Plex media over.

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2 hours ago, CoveVid said:

Thanks for this thread. I ran into this issue with Plex and Drivepool and had a hunch it was due to Drivepool.

It's unfortunate that this was never put into the FAQ and I had to find out the hard way after spending 12+ hours moving my Plex media over.

Just configure the metadata to be stored elsewhere - it should really be on an SSD anyway, for speed. It should be defaulting to using the system (C:/) for metadata. Personally, I use a dedicated cheap and small (120GB Sandisk Plus) SSD for mine.

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