NTFS features supported/unsupported

Is there a list of NTFS features that might cause performance, corruption or compatibility problems when used with the Drobo or DroboPro? e.g. NTFS Sparse Files, volume compression, shadow copy, other features used by WHS, etc.?

If not, is it possible for the Drobo developers to develop such a list?


[quote=“bhoar, post:1, topic:501”]
Is there a list of NTFS features that might cause performance, corruption or compatibility problems when used with the Drobo or DroboPro? e.g. NTFS Sparse Files, volume compression, shadow copy, other features used by WHS, etc.?

If not, is it possible for the Drobo developers to develop such a list?[/quote]

Mark - any chance you can reply to this thread?


I am in the process of going thru a MAJOR headache right now with my Drobo in Windows 7 using the latest NTFS (8TB volume, so not Legacy NTFS):


I’ve noticed some strange behaviour while using MozyHome Remote Backup with its default settings which enable open files backup. I’m sure it has something to do with VSS (Volume Shadow Copy Service). With this option enabled, Mozy, as a one of the first steps, tries to make a volume snapshot and that’s where the things are getting nasty. It causes every application trying to access Drobo to freeze, often causing very heavy CPU load, Dashboard included. At this time Drobo’s access LED glows very faintly, like there were many small data transfers. After some time watching this total freeze, I’ve cancelled the backup, which took some more time (Drobo still unresponsive). When everything was just about to “unfreeze”, Drobo has displayed red bay LED and free space critical alert, before volume shadow copy has apparently been released and the Drobo free space went back to normal. I can only speculate that the VSS mechanism maybe has tried to the snapshot the WHOLE volume which it thinks is 16TB big. I’m not sure why Mozy does that instead of snapshooting only the locked files and only when needed but I don’t know how the VSS works exactly, either.

Zbig’s comment is an example of exactly the concern I have: are things that should work, like VSS, going to be problematic with the drobo or drobopro?

@zbig, @bhoar – Is Mozy letting you backup a Drobo? From what I have read, a complaint about their service is that it is only for internal drives, i.e. external storage like a Drobo is excluded. When did this change?

there has been plenty of discussion about using Drobo with apps that want to read/write every block on the device. Drobo uses “thin provisioning”, which is a fancy term meaning it tells the OS its a bigger disk than it actually has in storage. In most cases this doesn’t make a difference. Some applications, most notably “full disk encryption systems” want to write data to every single block on the Drobo. Since Drobo goes into slow down mode when it passes 95% full (the final kick in the ass to the user to add a drive) these apps fail. Its a conflict between software and hardware. Have you asked Mozy, what it does in this regard?

Looks like there are two flavours of the USB/FW connected storage class devices: one which mounts as a fixed drive (the icon like for the internal drive, trash can support, hidden “System Volume Information” folder, and so on) and the other, which mounts under “Drives with removable storage” category, with different icon). It seems that Mozy doesn’t differentiate the Drobo from other fixed drives because it mounts as the first one.

Right, I’m fully aware of that. That’s why I would never try using dynamically expanding, sparse file-based (or any kind of partition-based) TrueCrypt volume - there’s just too much mess that could cause having im mind the way Drobo works. Speaking of which, by the way, you can mount a TrueCrypt volume as either “fixed” or “removable”. But for Mozy - that’s another story and I’m not even blaming Drobo. First of all, what I’ve tried to back up is a bunch (~30GB) of photo files, none of which was locked in any way at the time of the backup operation. That’s why I don’t understand, why on earth Mozy is trying to snapshot the whole frickin’ drive (that’s how it looks like) just because it had an “Open files backup support” checkbox enabled. Again, I’m not sure how exactly does VSS work, but I was pretty sure that when it would came across some locked file, it would request this and only this file’s shadow copy from the VSS mechanism. Anyway, I’ve just disabled open file support in Mozy as I couldn’t think of any kind of data I would want to backup while having it open for now and this way Mozy and Drobo are playing nice with each other.


this sounds very much like the issue I have experienced. See also here: http://www.drobospace.com/forums/showthread.php?tid=93&pid=12181#pid12181

hi, sorry this is older thread but just fyi, ive been using Mozy with my Gen1 4-slot drobo and its been ok with all the options ticked.

(what i did notince in the past was that it can take a while and slow things down if i use its default “backups sets” - because it takes ages trying to scan the whole drives for files that match it’s default sets.

(with those disabled, its been working fine for 35k files across a mixture of sizes, icon clipart libraries, digipics, samples, and multimedia productions etc) (35,000 files of about 17GB total) - aprt from the odd message glitch or when wireless plays up, its been fine over here.

one think you could try is to make 1 new folder in your root drobo, put a few files into it, and then go up a level (back to root) and rightclick on the new folder choosing Add To Mozy Backup.
then when you go inside that folder and refresh, it should show you the icons to show that its planned for, but not yet included in, the next backup run.

as far as i know, if you modify one of those files, or if you add something to the folder, Mozy “should” detect it and inlclude it in the next run (and you can always manually initiate a run).

If the 1 folder trick works, (maybe if you do end up having some files open/locked, you could try removing your backups sets and just setting it up on that 1 folder) - or to have several of those main backup folders which you can use in this way.

just some thoughts/info from my usage and experience :)[hr]
(info for zbig mainly) :slight_smile: