DSM-G600, DNS-3xx and NSA-220 Hack Forum

1) Yes, sort of, not really.  I have a module for NTFS, but extreme caution has to be used with it.  I was using it to access a USB hard drive that was NTFS.  Unfortunately the DNS went unstable one time trying to copy or move something, I really cannot remember now.  Anyway, it ended up locking up the box and on reboot, I had lost access to all the data.  It seems the data itself was there, but what would be the equivelant to the fat table (not super familure with NTFS structure) was corupt, so the OS did not know where anything was.  Long story short, I lost 300 GB of data.  Luckily I keep backups, so no harm.

2) True.  Through tests, RAID 0 on this device does not give any substantial benefit over standard, however it puts your data at major risk.  (Search the forum, you will find the test results several times.)  If you fail 1 drive, you lose all data on both.  JBOD might save some data in a failure, but I doubt it.  I think you will be in the same boat.  Besides, why do you need 1 giant drive, unless you are working with a few really large files in the order of 300 GB or more each.  In my opinion, only RAID 1 or standard are useful on this device.  The others are really no more than a marketing gimik.

3) Yes, but why?  Have 2 separate drives and only lose part of the data if a drive fails.

4) In theory.  But there is something that requires a complete re-format of all the drives once upgraded to 1.04 in order to make it work properly.

5) Probably instability.  If you search the forum, there were a lot of complaints of data loss with EXT3 and 1.02.  I assume it was removed for this reason.  bspvette86 is testing EXT3 in 1.05 right now.  He is doing it via fun_plug, it is not D-Link official.  The link to the forum is here: http://dns323.kood.org/forum/t2225-Anyo … S-323.html

He didn't say you'll lose all your data with JBOD - what he said is it might save some data in a failure, but that he doubted it.

Here is what happens and yes I am 100% certain.

Hardware Rev A1, firmware Rev 1.05, 2x80GB Maxtor drives in JBOD.

For the first test I hot unplugged the left drive - based on the assumption that the DNS-323 will store data on the right drive first - after a few minutes the amber LED turns on & the unit sends an email saying the left drive has failed.  The data is still available.  Reboot the DNS-323 and attempt to retrieve the data and Windows returns a message saying the resource is not available.  Prior to the reboot, the DNS-323 status screen shows no indication of a problem and after the reboot it shows 1 drive and no volumes.

I then deleted the partitions from the removed drive and re-installed it - at the next login, the format prompt appears and if you click next the DNS-323 formats both drives.

For the second test I powered the DNS-323 down before removing a drive, again the left drive (after all, pulling the right one guarantees that the data won't be available - at least not until I've written more than 80 GB to the unit) - not surprisingly, there is no amber LED, no email alert - and no data - Windows returns the same error message as before, and the status screen again shows one drive and no volumes.

An attempt to mount the right drive (which contains the data) using a Windows system and ext2ifs results in a message telling me the drive is unformatted and of course an offer to format it - this combination by the way will usually allow data to be retrieved from a disk removed from a RAID1 array or a standard volume.

I could, I suppose, repeat the tests and instead pull the right drive, but I don't really see a point in it - I've already established that the DNS-323 writes to that disk first and so if that disk were to fail, you know for certain you'd be losing the data on it, and based on the results of this test, that you stand a good chance of losing it all.

If you actually want/need a single large share, then just use JBOD - I avoid RAID-0 and JBOD because I feel that it doubles my risk of loosing *all* of my data because the whole filesystem will break if one of the disks dies. Two disks = twice the chance of failure (approximately!)

JBOD *might* make it possible to recover some data from if one disk goes down (I don't think anyone here has ever said how though ...)

However, even with two Standard volumes the chances of loosing *some* data to a disk failure are exactly the same as with JBOD.

So, do you think this would make a good signature for this forum ;-)
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If you want or need a single volume use JBOD, if you don't, use Standard.

If you need high availability of your data use RAID-1, if you don't, then use Standard.

If your data is time-consuming, expensive or impossible to restore, then keep backups.

[EDIT: Prefer this version:]
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If you need high availability of your data use RAID-1; if you want or need a single big volume use JBOD; otherwise use Standard.

If your data is time-consuming, expensive or impossible to restore, then keep backups.

Last edited by sjmac (2008-05-21 12:29:57)

Let's assume for a second we don't have 1TB hard drives, what would you do if you really want JBOD? You probably buy two 500GB drives, right? Great, now buy two 1TB drives and use only one drive to store your music, and you get another volume to store whatever else you want! You are no worse off than using two 500GB drives, and your data will be safer with two separate, standard volumes too!

I'm sure my reasoning doesn't make sense to a lot of people...

huge music archive here: approximately 1.6tb of flac files. it is very demanding to manage (dupechecking, proper naming and stuff) this ammount of data (files) and breaking it into directories (multiple disks) just makes things even more harder. i think i will wait for dns-343 or intel ss4200-e (http://www.intel.com/design/servers/sto … /index.htm) and use raid 0+1 or raid5